John Locke (1632–1704) stands as a towering figure in Western philosophy, renowned as a British philosopher, Oxford academic, and medical researcher whose profound John Locke Ideas have shaped modern thought. His seminal work, An Essay Concerning Human Understanding (1689), is a cornerstone of modern empiricism, meticulously investigating the scope and limits of human comprehension across diverse subjects. In essence, Locke sought to delineate what humans can confidently claim to know and what remains beyond the grasp of our understanding.
Locke’s association with Anthony Ashley Cooper, later the First Earl of Shaftesbury, propelled him into the realm of government and politics. He served as a government official, gathering crucial information about trade and colonies, became an influential economic writer, an active political opponent, and ultimately a revolutionary whose principles found triumph in the Glorious Revolution of 1688. Among his vast political writings, The Second Treatise of Government remains his most celebrated. In it, Locke masterfully argues for popular sovereignty, asserting that ultimate authority resides in the people. He meticulously outlines the nature of legitimate government grounded in natural rights and the social contract, foundational john locke ideas that continue to resonate today. Further solidifying his commitment to individual liberty, Locke famously advocated for the separation of Church and State in his Letter Concerning Toleration.
A defining characteristic of john locke ideas is his staunch opposition to authoritarianism in all its forms. This resistance permeates his work, whether considering the individual or societal institutions like government and the church. For Locke, individual autonomy was paramount. He urged each person to employ reason as their guide in the pursuit of truth, rejecting blind acceptance of authority or the shackles of superstition. He championed the idea that belief should be proportional to evidence. At an institutional level, Locke stressed the critical need to distinguish between the legitimate and illegitimate functions of power structures, particularly concerning the justifiable use of force. Locke firmly believed that the application of reason to understand truth and define the rightful roles of institutions is the pathway to maximizing human flourishing, both individually and collectively, encompassing both material and spiritual well-being. This, in Locke’s view, aligns with natural law and fulfills humanity’s divine purpose.
1. John Locke: Life and Context of His Ideas
John Locke’s intellectual and political john locke ideas were forged in the crucible of 17th-century England, a period of immense upheaval and transformation. Born in 1632 and living until 1704, Locke witnessed and participated in one of the most turbulent and intellectually fertile centuries in English history. This era was defined by intense conflicts between the Crown and Parliament, intertwined with religious strife among Protestants, Anglicans, and Catholics, culminating in the English Civil War in the 1640s. The execution of Charles I ushered in a radical experiment in governance, including the abolition of the monarchy, the House of Lords, and the Anglican Church, and the rise of Oliver Cromwell’s Protectorate in the 1650s.
The Protectorate’s collapse after Cromwell’s death paved the way for the Restoration of Charles II in 1660, reinstating the monarchy, the House of Lords, and the Anglican Church. However, this restoration did not quell the underlying tensions. The period from 1660 to 1688 remained marked by ongoing power struggles between the King and Parliament, as well as fervent debates regarding religious toleration for both Protestant dissenters and Catholics. This tumultuous period concluded with the Glorious Revolution of 1688, which saw James II deposed and replaced by William of Orange and his wife Mary. Locke’s later years were spent during the consolidation of William and Mary’s reign and the beginning of England’s involvement in European power struggles against Louis XIV’s France, setting the stage for the military successes of figures like John Churchill, the Duke of Marlborough. These historical events profoundly shaped john locke ideas, particularly his views on government, liberty, and toleration.
1.1 Formative Years: Locke’s Early Life and Education (1632-1666)
Born in Wrington to Puritan parents of modest means, John Locke’s early life provided the bedrock for his later john locke ideas. His father, a country lawyer, served in the Puritan cavalry during the English Civil War. Crucially, his father’s commander, Alexander Popham, became the local Member of Parliament and a vital patron, ensuring young John received an exceptional education. In 1647, Locke began his formal education at Westminster School in London, a prestigious institution that laid the foundation for his intellectual pursuits.
In the autumn of 1652, at the age of twenty, Locke matriculated to Christ Church, Oxford, then the most prominent college within the preeminent English university. Despite Oxford’s standing, its educational approach remained rooted in medieval Aristotelian philosophy, which Locke, like Hobbes before him, found increasingly irrelevant and unstimulating. However, Oxford was not solely confined to Aristotelianism. The burgeoning “new experimental philosophy” had begun to take hold. John Wilkins, Cromwell’s brother-in-law, became Warden of Wadham College and fostered a group that would become the nucleus of the English Royal Society. This society, initially an informal gathering for discussion, formally coalesced in London after the Restoration in the 1660s, receiving royal charters from Charles II. The Royal Society distinguished itself by prioritizing the study of nature through observation and experimentation, a stark contrast to the text-based Scholastic and Aristotelian traditions dominating universities. This emphasis on empirical investigation deeply influenced john locke ideas about knowledge and understanding.
Many associates of Wilkins were drawn to medicine, favoring observation-based practice over reliance on classical texts. Francis Bacon’s advocacy for meticulous experimentation and systematic data collection to derive generalizations resonated strongly within this circle. Richard Lower, a friend from Westminster, introduced Locke to medicine and the experimental philosophy embraced by the intellectual circles at Wadham.
Locke earned his Bachelor of Arts degree in February 1656 and continued his Oxford career, receiving a Master of Arts in June 1658 and being elected a Senior Student at Christ Church College. This position, equivalent to a Fellowship at other colleges, was not permanent, leaving Locke to contemplate his future path. He served as Lecturer in Greek at Christ Church from December 1660 and in Rhetoric from 1663. A career decision loomed: Christ Church statutes mandated that the majority of senior studentships be reserved for clergy or those pursuing ordination. With limited slots for other professions (medicine, law, moral philosophy), the clergy appeared a logical choice. Yet, Locke had been increasingly drawn to medicine since his graduation and ultimately resolved to become a physician.
John Wilkins’ departure from Oxford after the Restoration shifted the leadership of the Oxford scientific group to Robert Boyle, who became Locke’s scientific mentor. Boyle, with his assistant Robert Hooke, was instrumental in experimental science. They constructed an air pump that led to Boyle’s Law and invented a barometer for weather prediction. Boyle’s air pump experiments sparked a decade-long controversy with Thomas Hobbes because Boyle’s explanations clashed with Hobbes’ micro-corpuscular theory. Boyle’s theoretical contributions were equally significant. He was a mechanical philosopher, viewing the world as fundamentally reducible to matter in motion, though he lacked a micro-corpuscular explanation of air itself.
Locke encountered Boyle’s work before engaging with Descartes. Upon reading Descartes, Locke recognized the French philosopher as offering a compelling alternative to the Aristotelian scholasticism he had found so limiting at Oxford. In writing An Essay Concerning Human Understanding, Locke adopted Descartes’ “way of ideas,” transforming and integrating it into the core of his own philosophical framework. However, his immersion in the Oxford scientific community instilled a critical perspective on the rationalist aspects of Descartes’ philosophy, shaping key john locke ideas about the nature of knowledge acquisition.
In his Epistle to the Reader at the beginning of the Essay, Locke humbly positions himself within the burgeoning scientific revolution:
The commonwealth of learning is not at this time without master-builders, whose mighty designs, in advancing the sciences, will leave lasting monuments to the admiration of posterity: but everyone must not hope to be a Boyle or a Sydenham; and in an age that produces such masters as the great Huygenius and the incomparable Mr. Newton, with some others of that strain, it is ambition enough to be employed as an under-labourer in clearing the ground a little, and removing some of the rubbish that lies in the way to knowledge …. (N: 9–10)
Locke was personally acquainted with Boyle, Sydenham, Huygens, and Newton, all central figures in the scientific revolution. He, Boyle, and Newton were all founding or early members of the English Royal Society. From Boyle, Locke learned about atomism (the corpuscular hypothesis) and adopted the language of primary and secondary qualities from Boyle’s The Origin of Forms and Qualities. Thomas Sydenham, an English physician with whom Locke conducted medical research, championed careful disease observation and rejected abstract causal explanations. Boyle and Newton also conducted color research that moved beyond micro-corpuscular explanations. While in exile in Holland, Locke studied Newton’s Principia Mathematica Philosophiae Naturalis, consulting Huygens on its mathematical rigor. After Locke’s return to England in 1688, he and Newton became friends. Locke’s self-description as an “under-laborer” might reflect not only literary modesty but also a contrast between the groundbreaking discoveries of these scientific giants and his own project of critiquing Aristotelian, Scholastic, and, to some extent, Cartesian philosophies. However, this self-deprecating image understates the breadth and depth of Locke’s philosophical contributions (Jolley 1999: 15–17). While corpuscular philosophy and Newtonian science significantly influenced Locke, he explicitly references Bacon’s program of producing natural histories in the Introduction to the Essay. He writes:
It shall suffice to my present Purpose, to consider the discerning Faculties of a Man, as they are employ’d about the Objects, which they have to do with: and I shall imagine that I have not wholly misimploy’d my self in the Thoughts I shall have on this Occasion, if in this Historical, Plain Method, I can give any Account of the Ways, whereby our Understanding comes to attain those Notions of Things, and can set down any Measure of the Certainty of our Knowledge…. (I.1.2, N: 43–4)
The ‘Historical, Plain Method’ signals Locke’s intent to provide a genetic account of how we acquire ideas, aiming to reveal the certainty of knowledge derived from them. Locke’s direct engagement with the scientific movement was primarily through informal medical studies. He collaborated closely with Dr. David Thomas, and they maintained a laboratory in Oxford, likely functioning as a pharmacy. In 1666, a pivotal encounter occurred when Lord Ashley, one of England’s wealthiest men, visited Oxford seeking medicinal waters and requested Dr. Thomas’s assistance. When Thomas was unavailable, Locke stepped in to ensure the water was delivered. This meeting led to Ashley inviting Locke to London as his personal physician. In 1667, Locke moved to London, becoming not just Lord Ashley’s physician, but also his secretary, researcher, political advisor, and close friend. Living with Ashley placed Locke at the very center of English politics during the 1670s and 1680s, deeply shaping his political john locke ideas.
1.2 Locke and Lord Shaftesbury: Political Engagement and Exile (1666-1688)
Locke’s primary role upon joining Lord Ashley’s household at Exeter House in 1668 was as his personal physician. He demonstrated his medical acumen by successfully organizing and overseeing a complex operation on Ashley, perhaps the most meticulously documented surgery of the 17th century. Locke consulted extensively with physicians across England to determine best practices and prioritized hygiene, ultimately saving his patron’s life and arguably altering the course of English history. This practical experience further honed john locke ideas on observation, evidence, and effective action.
Beyond medicine, Locke took on diverse responsibilities. He served as secretary of the Board of Trade and Plantations and Secretary to the Lords Proprietors of the Carolinas. Lord Ashley, a proponent of England’s prosperity through trade and colonies, convinced Charles II to establish the Board of Trade and Plantations to gather information on these matters. Locke became its secretary, making him a central hub for global trade and colonial intelligence for the English government. Ashley’s colonial ambitions extended to the Carolinas, and as secretary to the Lords Proprietors, Locke played a role in drafting the fundamental constitution for the Carolinas, although the extent of his contribution remains debated. Locke’s involvement with trade and colonial administration provided him with practical insights into governance and economics, enriching his john locke ideas on these subjects.
Shaftesbury and Locke also collaborated on broader public policy issues, including a monetary crisis in England related to currency devaluation and coin clipping. Locke authored papers for Ashley on economic matters, including the coinage crisis, demonstrating his grasp of economic principles.
While immersed in political and administrative life in London, Locke maintained his philosophical pursuits. He recounts the genesis of An Essay Concerning Human Understanding:
Were it fit to trouble thee with the history of this Essay, I should tell thee, that five or six friends meeting at my chamber, and discoursing on a subject very remote from this, found themselves quickly at a stand, by the difficulties that rose on every side. After we had awhile puzzled ourselves, without coming any nearer a resolution of those doubts which perplexed us, it came into my thoughts that we took a wrong course; and that before we set ourselves upon inquiries of that nature, it was necessary to examine our own abilities, and see what objects our understandings were, or were not, fitted to deal with. This I proposed to the company, who all readily assented; and thereupon it was agreed that this should be our first inquiry. Some hasty and undigested thoughts, on a subject I had never before considered, which I set down against our next meeting, gave the first entrance into this Discourse; which having been thus begun by chance, was continued by intreaty; written by incoherent parcels; and after long intervals of neglect, resumed again, as my humour or occasions permitted; and at last, in a retirement where an attendance on my health gave me leisure, it was brought into that order thou now seest it. (Epistle to the Reader, N: 7)
James Tyrrell, a friend of Locke’s present at that meeting, recalled the discussion centered on morality and revealed religion (Cranston 1957: 140–1). This casual intellectual gathering marked the beginning of a philosophical endeavor that would occupy Locke intermittently for two decades.
In 1674, after Shaftesbury left government, Locke returned to Oxford, earning a Bachelor of Medicine degree and a license to practice medicine, before traveling to France (Cranston 1957: 160). He journeyed from Calais to Paris, Lyons, and Montpellier, spending fifteen months in France, largely studying Protestantism. The Edict of Nantes (1598) granted a degree of religious toleration in France, though this was soon to end with Louis XIV’s revocation in 1685 and the subsequent persecution of French Protestants. Locke’s observations of religious dynamics in France further informed his john locke ideas on toleration.
During Locke’s time in France, Shaftesbury’s political fortunes fluctuated dramatically. In 1676, Shaftesbury was imprisoned in the Tower of London for a year. In 1678, amidst the Popish Plot hysteria, informers like Titus Oates fabricated a Catholic conspiracy to assassinate the King and install his Catholic brother on the throne. Shaftesbury, while not initiating the conspiracy, exploited the public anti-Catholic fervor to advance his party’s agenda. He built a strong political network, exerted influence over elections, and gained a parliamentary majority. His key objective was to pass an Exclusion Bill preventing Charles II’s Catholic brother, James, from succeeding to the throne. Despite passing the Commons, the Exclusion Bill was defeated in the House of Lords due to the King’s opposition. As the Popish Plot panic subsided, Shaftesbury lost political traction. In 1681, he was again imprisoned in the Tower, tried for treason on fabricated charges, but acquitted by a London grand jury sympathetic to his cause.
Some Country Party leaders, disillusioned with parliamentary means, began plotting an armed insurrection, including a plan to assassinate Charles and James. Shaftesbury, moving between safe houses, eventually fled to Holland in November 1682, dying there in January 1683. Locke remained in England until the Rye House Plot (a plan to ambush and assassinate the King and his brother) was uncovered in June 1683. Locke left for the West Country to settle his affairs and by September was in exile in Holland. This period of political turmoil and Locke’s association with Shaftesbury were crucial in shaping his john locke ideas about government, resistance, and revolution.
While in exile in Holland, Locke completed An Essay Concerning Human Understanding and published a French précis of it, providing continental intellectuals with their primary information about the Essay until a full French translation appeared in 1704. He also wrote and published Epistola de Tolerentia in Latin. Richard Ashcraft’s Revolutionary Politics and Locke’s Two Treatises of Government (1986) suggests that Locke was deeply involved with English revolutionaries in exile, not just finishing philosophical works and recovering his health. The English government was concerned about this group and attempted to extradite several members, including Locke, leading to the revocation of his Oxford studentship. English intelligence infiltrated the rebel group, hindering their efforts, at least temporarily. During Locke’s exile, Charles II died in 1685 and was succeeded by James II. Soon after, the exiles launched a revolt under the Duke of Monmouth to overthrow James II, but it was crushed, and Monmouth was executed (Ashcraft 1986). Roger Woolhouse’s Locke: A Biography (2007) provides a detailed examination of Locke’s involvement with these exiled rebels.
Ultimately, the exiles’ efforts contributed to the Glorious Revolution. James II alienated much of his support, and William of Orange was invited to England with a Dutch force. James II, facing overwhelming opposition, fled to exile in France in 1688. This Glorious Revolution significantly shifted the balance of power in English government from the monarchy to Parliament. Locke returned to England in February 1689, his john locke ideas poised to become profoundly influential in the new political landscape.
1.3 Final Years and Legacy (1689-1704)
Following his return from exile, Locke published An Essay Concerning Human Understanding and Two Treatises of Government. Popple’s translation of A Letter Concerning Toleration also appeared. Notably, Two Treatises and Letter Concerning Toleration were published anonymously. Locke took residence at Oates in Essex, the home of Sir Francis and Lady Masham (Damaris Cudworth). Locke had developed a deep intellectual and romantic relationship with Damaris Cudworth, daughter of Cambridge Platonist Ralph Cudworth and a philosopher in her own right, since 1682. Despite her marriage to Sir Francis Masham in 1683 after Locke went into exile, Locke and Lady Masham remained close friends and intellectual companions for the rest of his life.
In his later years, Locke oversaw four more editions of the Essay and engaged in significant intellectual debates, notably in published letters with Edward Stillingfleet, Bishop of Worcester, regarding the Essay. He also defended Letter Concerning Toleration against various critiques. During this period, he wrote The Reasonableness of Christianity and Some Thoughts on Education.
Locke’s public service was not over. In 1696, the Board of Trade was revived, and Locke played a crucial role in its re-establishment, becoming its most influential member until 1700. The new Board of Trade possessed administrative power and addressed a wide range of issues, from the Irish wool trade and piracy suppression to poverty in England and colonial governance. Peter Laslett described it as “the body which administered the United States before the American Revolution” (Laslett 1954 [1990: 127]). Despite suffering from asthma in his final eight years, which limited his ability to endure London’s air pollution during warmer months, Locke dedicated himself to the Board out of a strong sense of civic duty. After retiring from the Board of Trade in 1700, Locke remained in retirement at Oates until his death on Sunday, October 28, 1704. His enduring legacy rests firmly on his vast and influential body of work, particularly his articulation of john locke ideas.
2. The Epistemology of John Locke: Understanding the Limits of Human Knowledge
Locke is frequently recognized as the foundational figure of British Empiricism, though the claims of Bacon and Hobbes are also considered. This reputation is primarily built upon his magnum opus, An Essay Concerning Human Understanding. Locke articulates his philosophical project in various sections of the Essay, with a central aim to define the boundaries of human understanding, a core tenet of john locke ideas. He states:
For I thought that the first Step towards satisfying the several Enquiries, the Mind of Man was apt to run into, was, to take a Survey of our own Understandings, examine our own Powers, and see to what Things they were adapted. Till that was done, I suspected that we began at the wrong end, and in vain sought for Satisfaction in a quiet and secure Possession of Truths, that most concern’d us whilst we let loose our Thoughts into the vast Ocean of Being, as if all the boundless Extent, were the natural and undoubted Possessions of our Understandings, wherein there was nothing that escaped its Decisions, or that escaped its Comprehension. Thus Men, extending their Enquiries beyond their Capacities, and letting their Thoughts wander into those depths where they can find no sure Footing; ’tis no Wonder, that they raise Questions and multiply Disputes, which never coming to any clear Resolution, are proper to only continue and increase their Doubts, and to confirm them at last in a perfect Skepticism. Wheras were the Capacities of our Understanding well considered, the Extent of our Knowledge once discovered, and the Horizon found, which sets the boundary between the enlightened and the dark Parts of Things; between what is and what is not comprehensible by us, Men would perhaps with less scruple acquiesce in the avow’d Ignorance of the one; and employ their Thoughts and Discourse, with more Advantage and Satisfaction in the other. (I.1.7, N: 47)
While earlier philosophers had hinted at the importance of understanding the limits of human intellect, Locke systematically and comprehensively pursued this project. In the four books of the Essay, he examines the origins and nature of human knowledge, foundational john locke ideas in epistemology. Book I refutes the notion of innate knowledge, aligning him with Berkeley and Hume and contrasting with Descartes and Leibniz. Locke posits that the human mind at birth is essentially a blank slate, a tabula rasa, upon which experience inscribes knowledge. Book II asserts that ideas are the fundamental building blocks of knowledge, and all ideas derive from experience. Locke defines ‘idea’ broadly as “…whatsoever is the Object of the Understanding, when a man thinks” (I.1.8, N: 47). Experience is twofold: sensation, providing information about the external world, and reflection, an internal sense that makes us conscious of our own mental operations. Some ideas originate solely from sensation, some from reflection, and others from both.
Locke proposes an atomistic, or more accurately, a corpuscular theory of ideas, drawing an analogy between atoms combining into physical objects and ideas combining into complex concepts. Ideas are categorized as simple or complex. We cannot invent simple ideas; they are solely derived from experience. In this process, the mind is passive. However, once equipped with simple ideas, the mind actively combines them into complex ideas of various types, including ideas of substances and modes. Substances are independent entities (God, humans, animals, plants, artifacts), while modes are dependent existences (mathematical, moral, conventional ideas). The mind also relates ideas, simple or complex, to perceive connections and differences, giving rise to ideas of relations (II.12.1, N: 163). Abstraction, another mental operation, generates general ideas from particulars by omitting specific details of time and place, allowing for broader application. Faculties like memory enable idea storage. This framework of idea formation is central to john locke ideas on how we acquire knowledge.
Having outlined the mechanisms for deriving simple and complex ideas of substances, modes, relations, and so on, Locke elucidates the origins of specific ideas like solidity, number, space, time, power, identity, and moral relations from sensation and reflection. His chapter on power explores free will and voluntary action (see the entry on Locke on freedom). Locke also offered groundbreaking perspectives in the philosophy of mind, suggesting, for instance, that God could equally imbue matter, properly organized, with perception and thought as He could attach these powers to an immaterial substance linked to matter. His account of personal identity in II. xxvii was revolutionary (see Locke on personal identity). These and related topics are further explored in the supplementary document: Some Interesting Issues in Locke’s Philosophy of Mind.
The following discussion focuses on key aspects of Locke’s account of physical objects. (See also Locke’s philosophy of science for related topics beyond this general overview, including Locke’s views on knowledge in natural philosophy, corpuscular philosophy limitations, and his relationship with Newton).
Locke’s understanding of physical objects is rooted in mechanical philosophy and the corpuscular hypothesis. Mechanical philosophy explained material phenomena through matter in motion and impact, viewing matter as passive and rejecting “occult qualities” and “action at a distance” of Aristotelian and Scholastic traditions. Robert Boyle’s corpuscularian hypothesis posited that the material world is composed of particles. Some corpuscularians believed particles could be further divided and the universe was filled with matter without void space. Atomists, conversely, held particles to be indivisible, composing a world of atoms and void space for their movement. Locke was an atomist, and atomism is crucial to understanding john locke ideas about the material world.
Atoms possess properties: extension, solidity, shape, motion, or rest. They combine to form familiar substances and objects: gold, wood, animals, plants, tables, chairs. These objects also have properties: extension, solidity, shape, motion, and rest, shared with their constituent atoms. Additionally, they possess properties like colors, smells, and tastes, arising from their interaction with perceivers. This distinction between property types traces back to Greek atomists, articulated by Galileo and Descartes, and notably by Locke’s mentor, Robert Boyle.
Locke formalizes this distinction in Book II, Chapter 8 of the Essay, adopting Boyle’s terminology of primary and secondary qualities. This distinction is fundamental to both major branches of mechanical philosophy in the 17th and early 18th centuries—Cartesian plenum theorists (infinitely divisible matter, no void) and atomists like Gassendi (indivisible atoms, void space). However, differences between these branches impact their accounts of primary qualities. In his chapter on Solidity (II.4), Locke rejects the Cartesian definition of body as mere extension, arguing that bodies are both extended and impenetrable or solid. Solidity in Locke’s account distinguishes bodies from void space, a key aspect of john locke ideas regarding matter.
Primary qualities of an object are inherent, independent of perception: occupying space, motion or rest, solidity, and texture. Secondary qualities are powers in bodies to produce ideas in us, such as color, taste, smell, triggered by our perceptual apparatus interacting with primary qualities. Our ideas of primary qualities resemble the qualities themselves, while ideas of secondary qualities do not resemble their causes. Locke also identifies a second class of secondary properties: powers of one substance to affect another (e.g., fire melting wax).
Scholarly debate surrounds the intricacies of Locke’s primary/secondary quality distinction. Issues include: which qualities belong to each category (Locke provides multiple lists), the criteria for categorization (sense-based distinction?), whether only atoms have primary qualities or compounds also do, and the meaning of ‘resemblance’ between ideas of primary qualities and the qualities themselves. Related is the question of how we know about imperceptible particles. Locke suggests analogies between macroscopic objects (porphyry, manna) and their constituent particles, a process Maurice Mandelbaum termed ‘transdiction’. These analogies allow inferences about particle nature, e.g., atoms are solid, heat is rapid atomic motion, cold is slower motion. However, these analogies may not fully reveal necessary connections between qualities in nature. Another debated point is whether Locke’s distinction is reductionistic. If reductionism means primary qualities are fundamental and explain secondary qualities, the answer is unclear. Secondary qualities are surely primary qualities affecting us in specific ways, seemingly reductionistic. Yet, Locke’s “real ideas” in II.30 include both primary and secondary qualities. While secondary quality ideas are caused by primary qualities, primary qualities do not fully explain them. Locke argues we cannot conceive how particle size, shape, and motion cause sensation. Knowing particle properties offers no insight into sensory experience (IV.3.11–40, N: 544–546). These nuances highlight the complexity of john locke ideas on perception and the material world.
Locke likely holds a representational theory of perception, though scholarly consensus is not absolute. This theory posits that the mind directly perceives ideas, which are caused by and represent external objects. Perception is a triadic relation (object-idea-perceiver) rather than a dyadic one (object-perceiver) of naive realism. Naive realism suggests direct object perception, but faces objections. Representational theory versions also face criticisms. If ideas are treated as entities, they could be seen as obstructing perception of external objects – the “picture/original” or “veil of perception” theory. Nicholas Malebranche, a Cartesian follower, arguably held such a view. Antoine Arnauld, while believing in representative ideas, was a direct realist about perception, criticizing Malebranche. Locke follows Arnauld in this critique (Locke, 1823, Vol. IX: 250). Berkeley, and later commentators like Bennett, attributed the veil of perception interpretation to Locke. A.D. Woozley succinctly captures the dilemma:
…it is scarcely credible both that Locke should be able to see and state so clearly the fundamental objection to the picture-original theory of sense perception, and that he should have held the same theory himself. (Woozley 1964: 27)
Locke’s exact theory of perception remains debated. A symposium in the Pacific Philosophical Quarterly (2004) found most participants agreeing Locke held a representative theory but was not a skeptic in the veil of perception sense. This ongoing debate underscores the richness and complexity of john locke ideas on perception.
Another long-standing controversy since the Essay‘s publication concerns Locke’s concept of ‘substance’. The primary/secondary quality distinction is helpful, but Locke grapples with what underlies or supports primary qualities. He also questions what material and immaterial substances share that justifies using the same term. These reflections led to the concept of substance in general, an “I know not what” supporting qualities that cannot exist independently. We experience clusters of properties, inferring a supporting substance, though we lack direct experience of it. Locke sees no alternative to substance supporting qualities, rejecting tropes (properties existing independently of substances) to avoid substance. He isn’t skeptical about ‘substance’ like Hume, but emphasizes the limitations of our substance ideas. Bishop Stillingfleet accused Locke of removing substance from the rational world, but Locke aimed to highlight the limits of our understanding, a recurring theme in john locke ideas.
Since Berkeley, Locke’s substratum or substance in general doctrine has been criticized as incoherent, implying a property-less particular, seemingly contradicting empiricism. We lack experience of such an entity, thus lacking an empirical basis for the idea. Locke acknowledges this (I.4.18, N: 95). Michael Ayers proposes understanding ‘substratum’ and ‘substance in general’ through Locke’s real and nominal essence distinction in Book III, rather than as separate problems. Real essence (atomic constitution) causally grounds observable properties, forming nominal essences. Real essences are unknown to us. Ayers interprets ‘substance in general’ as ‘whatever supports qualities’, and real essence as ‘specific atomic constitution explaining observable qualities’. Thus, the unknown substratum and real essence are the same, eliminating property-less particulars. This interpretation has been criticized for lacking textual support and conflicting with Locke’s statements (Jolley 1999: 71–3). As we reach Book III, we turn to Locke’s linguistic theories, another key aspect of john locke ideas.
2.3 Locke on Language: Words, Ideas, and Essences
Book III of An Essay Concerning Human Understanding is devoted to language, emphasizing its critical role in knowledge acquisition, a central component of john locke ideas. Locke starts by highlighting the importance of abstract general ideas for knowledge, serving as categories for classifying the vast array of particular existences. Abstract ideas and classification are thus central to Locke’s view of language and its role in knowledge. Without general terms and classes, knowing the world of particulars would be an impossible task.
Book II and III are linked by Locke’s assertion that words stand for ideas. His discussion of language categorizes words according to idea types established in Book II: substances, simple modes, mixed modes, relations, etc. Here, Locke introduces the real and nominal essence distinction. Perhaps due to his focus on kind terms in classification, Locke emphasizes nouns over verbs. He acknowledges particles, words that “…signify the connexion that the Mind gives to Ideas, or Propositions, one with another” (II.7.1, N: 471), but word-idea relations dominate Book III.
Norman Kretzmann terms “words in their primary or immediate signification signify nothing but the ideas in the mind of him that uses them” (III.2.2) as “Locke’s main semantic thesis” (Kretzmann 1968:179). This has been criticized as a semantic blunder. Mill, for example, argued, “When I say, ‘the sun is the cause of the day’, I do not mean that my idea of the sun causes or excites in me the idea of day” (Mill 1843: bk 1, ch. 2, § 1). This critique parallels the “veil of perception” critique, suggesting Locke conflates word meaning and reference. Kretzmann argues that Locke distinguishes meaning and reference, with ideas providing meaning, not reference, refuting the Mill-style criticism. This nuanced understanding of language is vital to grasping john locke ideas on communication and knowledge.
Besides idea types, Locke distinguishes particular and abstract ideas. Particular ideas include specific place and time, limiting application to a single instance. Abstract general ideas omit these details, allowing broader application. Abstraction and Locke’s account of it have been debated. Berkeley argued Locke’s abstraction is incoherent, partly due to Berkeley’s imagism (ideas are images). If ideas are images, imagining an idea encompassing both right and equilateral triangles seems impossible. Michael Ayers argues Locke was also an imagist, making Berkeley’s critique potent. However, Ayers’ claim is contested (Soles 1999). Abstraction is crucial for human knowledge; Locke believes most words are general (III.1.1, N: 409). Only general or sortal ideas can function in classification systems.
Locke’s discussion of substance names and their contrast with mode names reveals key aspects of his views on language and knowledge. Physical substances are atoms and atom-composed things. We lack direct experience of the atomic structure of horses and tables. We know them through secondary qualities (color, taste, smell) and primary qualities (shape, motion, extension). Since real essence (atomic constitution) of a horse is unknown, ‘horse’ cannot derive meaning from it. General words signify complexes of ideas we deem part of that sort’s idea, derived from experience. Locke calls such a general idea picking out a sort the nominal essence. This nominal essence concept is central to john locke ideas on language and classification.
Classification is a central issue in Book III. How do we categorize things into kinds and organize them into species and genera? Aristotelian and Scholastic traditions, rejected by Locke, emphasized necessary properties for an individual’s existence and persistence, contrasting with accidental properties. Shared necessary properties define natural kind essences. Kind boundaries were sharp and determinate. Aristotelian science aimed to discover natural kind essences, forming a unique, privileged hierarchical classification system reflecting world structure – Aristotelian essentialism. Locke rejects aspects of this doctrine, denying individual essences apart from kind membership and rejecting a single privileged natural classification. He argues for multiple valid classifications depending on purpose, a pragmatic view of language and classification fundamental to john locke ideas.
Locke’s pragmatic language account and nominal/real essence distinction offer an anti-essentialist alternative to Aristotelian essentialism and natural kind classification. He claims no fixed boundaries in nature to be discovered, no clear species demarcation, always borderline cases. Debate exists whether this lack of boundaries applies to both appearances/nominal essences and atomic constitutions/real essences, or only nominal essences. The first view is Locke denies Aristotelian natural kinds at both levels. The second is Locke believes in atomic-level Aristotelian natural kinds, but we cannot access or know them. In either view, real essence cannot provide substance name meaning. A.O. Lovejoy and David Wiggins support the second view; Michael Ayers and William Uzgalis the first (Uzgalis 1988; Ayers 1991: II. 70). This anti-essentialism is a key aspect of john locke ideas on knowledge and the world.
Nominal essences are derived from experience. Locke argues the mind actively constructs sort ideas, choosing from numerous properties, allowing diverse nominal essences for the same substance. This might suggest arbitrary and conventional sort-making, with no basis for criticizing nominal essences. Locke sometimes implies this. However, this impression should be resisted. Peter Anstey characterizes Locke’s conventionalism as both constrained and convergent (Anstey 2011: 209, 212). Locke states nominal essence making is understanding’s work, constrained by usage (words for existing ideas) and substance word’s supposed copying of substance properties. Locke says kind ideas are archetypes of property complexes producing appearances and causing idea complex unity. Archetypes imply constraints on property combinations. Without constraints, no archetype exists. (For further discussion, see Locke on Real Essences).
Word usage is a constraint. Shared meaning within language communities is vital for communication, language’s primary function. Misusing words hinders communication, defeating language’s purpose. Traditions of usage can evolve to improve knowledge and understanding through clearer, more determinate ideas.
Substance name creation involves discovery (e.g., violets, gold), naming the idea, and introducing it into language. Language is viewed as an instrument for everyday life. Ordinary people are language’s primary shapers.
Vulgar Notions suit vulgar Discourses; and both though confused enough, yet serve pretty well for the Market and the Wake. Merchants and Lovers, Cooks and Taylors, have Words wherewith to dispatch their ordinary affairs; and so, I think, might Philosophers and Disputants too, if they had a mind to understand and to be clearly understood. (III.11.10, N: 514)
Ordinary people use apparent qualities, mainly secondary qualities, to form ideas and words for their needs.
Natural philosophers (scientists) later investigate if property connections within ordinary ideas hold true in nature, seeking necessary property connections. However, even scientists, in Locke’s view, are limited to observable (mainly secondary) qualities for categorization. Scientists might correct popular errors, e.g., whales are mammals, not fish. Fish and mammal qualities differ; whales share mammal qualities. Classifying whales as fish is a mistake. Similarly, a limited gold idea (soft, gold-colored metal) fails to distinguish gold from fool’s gold. While the mind makes complex ideas (‘workmanship of understanding’), allowing free combination and naming, these products are open to criticism: non-conformity to usage or inadequate representation of archetypes. Criticism aims to improve understanding of the material world and the human condition – the convergent aspect of Locke’s conventionalism. Nominal essences converge on real essences through increased accuracy. This process reflects john locke ideas on scientific progress and language refinement.
However, we must remember Locke’s “master-builders.” Stephen Gaukroger (2010) argues Locke philosophically justified experimental philosophy (Boyle’s air pump, Boyle and Newton’s color research, Sydenham’s observational medicine), which was attacked for lacking matter theory explanations. Locke justifies experimental philosophy’s autonomy. Experimental explanations rely solely on phenomena relations, even with micro-corpuscular bases. Gaukroger sees this as Locke’s contribution to mechanism’s collapse. (See Gaukroger 2010, Chapters 4 and 5 for details).
The mode/substance distinction is central to john locke ideas. Modes are dependent existences, orderings of substances. Locke defines:
First, Modes I call such complex Ideas, which however compounded, contain not in themselves the supposition of subsisting by themselves; such are the ideas signified by the Words Triangle, Gratitude, Murther, etc. (II.12.4, N: 165)
Locke distinguishes simple and mixed modes:
Of these Modes, there are two sorts, which deserve distinct consideration. First, there are some that are only variations, or different combinations of the same simple Idea, without the mixture of any other, as a dozen or score; which are nothing but the ideas of so many distinct unities being added together, and these I call simple Modes, as being contained within the bounds of one simple Idea. Secondly, There are others, compounded of Ideas of several kinds, put together to make one complex one; v.g. Beauty, consisting of a certain combination of Colour and Figure, causing Delight to the Beholder; Theft, which being the concealed change of the Possession of any thing, without the consent of the Proprietor, contains, as is visible, a combination of several Ideas of several kinds; and these I call Mixed Modes. (II.12.5, N: 165)
Mode ideas are mind-made, archetype in mind. The question is whether world things fit our ideas, not vice versa. Mode ideas are adequate. ‘Bachelor’ is defined as unmarried, adult, male human. Mismatches don’t invalidate the definition, only indicate non-membership. Modes provide ideas of mathematics, morality, religion, politics, conventions. Modal ideas serve as standards; things fit or don’t fit, belonging or not. Mode ideas are clear, distinct, adequate, complete. Real and nominal essences merge in modes. Precise mathematical definitions (necessary and sufficient conditions) and deductive proofs are possible. Locke suggests morality is also demonstrably deductive, though he never produced such a system despite Molyneux’s urging. (See Locke’s moral philosophy). Political discourse terms also have modal aspects. Locke’s definitions of state of nature, slavery, war in Second Treatise are modal definitions allowing deductive consequences. Politics may require both experience and deductive modal aspects. This modal theory of knowledge is a significant facet of john locke ideas.
2.4 Knowledge, Probability, and the Limits of Certainty
In Book IV of An Essay Concerning Human Understanding, Locke defines knowledge, its scope, and human limitations, moving from idea formation to the nature and extent of knowledge, a culmination of john locke ideas. Locke defines knowledge as “the perception of the connexion and agreement or disagreement and repugnancy of any of our Ideas” (IV.1.1, N: 525). This contrasts with Descartes’ clarity and distinctness definition. Locke’s definition allows knowledge of substances despite the obscure substance in general idea. However, it raises a “veil of ideas” problem: are we trapped within our ideas, unable to know real existence? Locke likely believed the implausibility of skeptical hypotheses (Dream Hypothesis, not Evil Demon, which he omits), combined with causal connections between qualities and ideas, sufficiently addresses this. Locke’s empiricism differs from Berkeley’s, making the veil problem less acute for Locke. Locke makes transdictive inferences about atoms, which Berkeley rejects, implying Locke’s semantics allows talking about unexperienced causes of experience (atoms), unlike Berkeley. (See Mackie’s Problems from Locke, 1976: 51–67).
What can we know and with what certainty? God’s existence is knowable with demonstration-level assurance. Our own existence is known with highest certainty. Morality and mathematics are also certain, being modal ideas with adequacy guaranteed by our creation as ideal models, not copies of external archetypes. External object knowledge is limited to apparent quality connections. Elephant and gold real essences are hidden; we assume atomic combinations cause apparent quality groupings distinguishing elephants/violets, gold/lead as kinds. Material thing knowledge is probabilistic, opinion, not knowledge, inferior to mathematics, morality, self, and God knowledge. Sensitive knowledge of external objects is limited to present experience. While Locke sees limited knowledge, he believes we can judge truth/falsity of many propositions beyond knowledge, leading to probability. This distinction between knowledge and probability is crucial to john locke ideas on the scope and limits of human understanding.
2.5 Probability and Assent: Navigating the Twilight of Uncertainty
Knowledge involves perceiving idea agreement or disagreement. What is probability, and how does it relate to knowledge? Locke writes:
The Understanding Faculties being given to Man, not barely for Speculation, but also for the Conduct of his Life, Man would be at a great loss, if he had nothing to direct him, but what has the Certainty of true Knowledge… Therefore, as God has set some Things in broad day-light; as he has given us some certain Knowledge…So in the greater part of our Concernment, he has afforded us only the twilight, as I may say so, of Probability, suitable, I presume, to that State of Mediocrity and Probationership, he has been pleased to place us in here, wherein to check our over-confidence and presumption, we might by every day’s Experience be made sensible of our short sightedness and liableness to Error… (IV.14.1–2, N: 652)
Beyond a few certainties (self, God, math, morality), life is largely navigated without knowledge, in the realm of probability. Locke defines probability:
As Demonstration is the shewing of the agreement or disagreement of two Ideas, by the intervention of one or more Proofs, which have a constant, immutable, and visible connexion one with another: so Probability is nothing but the appearance of such an Agreement or Disagreement, by the intervention of Proofs, whose connection is not constant and immutable, or at least is not perceived to be so, but is or appears, for the most part to be so, and is enough to induce the Mind to judge the Proposition to be true, or false, rather than the contrary. (IV.15.1, N: 654)
Probable reasoning is argument-like, similar to demonstrative reasoning yielding knowledge, but with crucial differences. It provides evidence inclining the mind to judge a proposition true or false, without certainty. Probable judgment exists in degrees, from near certainty to near impossibility, correlating with assent degrees from full assurance to doubt and distrust.
Mathematical probability was emerging during Locke’s Essay writing, but his probability account shows little awareness of it, reflecting an older tradition treating testimony as probable reasoning. Given Locke’s focus on religious propositions, this older concept of probability likely better serves his purpose. Locke’s grounds for probability include proposition conformity to knowledge, observation, experience, and testimony of others. Testimony evaluation involves witness number, integrity, observational skill, counter-testimony, etc. Rational assent to probable propositions requires considering these factors. Locke also advises tolerance of differing opinions, favoring retaining existing opinions over adopting those of strangers or adversaries with potential biases.
Locke distinguishes two probable proposition types: particular existences/facts, and things beyond sense testimony. Facts are observable, allowing application of the above tests for rational assent. Things beyond sense are different: finite immaterial spirits (angels), atoms, distant planets’ life. For these, Locke says analogy is our only reasoning aid:
Thus the observing that the bare rubbing of two bodies violently one upon the other, produce heat, and very often fire it self, we have reason to think, that what we call Heat and Fire consist of the violent agitation of the imperceptible minute parts of the burning matter…. (IV.16.12, N: 665–6)
We reason about angels via the Great Chain of Being, assuming species above us are as numerous as those below. This reasoning is probabilistic. This exploration of probability showcases john locke ideas on navigating uncertainty and forming rational beliefs beyond certain knowledge.
2.6 Reason, Faith, and Enthusiasm: Balancing Belief and Evidence
The relative roles of senses, reason, and faith in attaining truth and guiding life were major 17th-century issues. Tyrrell noted the Essay‘s impetus was a discussion of morality and revealed religion. In Book IV, Chapters 17-19, Locke addresses reason, faith, and enthusiasm. Locke observes all sects use reason when possible, resorting to faith claiming revelation is above reason when reason fails. But, he adds:
And I do not see how they can argue with anyone or even convince a gainsayer who uses the same plea, without setting down strict boundaries between faith and reason. (IV.18.2, N: 689)
Locke defines reason as
the discovery of the certainty or probability of such propositions or truths, which the mind arrives at by deduction made from such ideas, as it has got by the use of its natural faculties; viz, by the use of sensation or reflection. (IV.18.2, N: 689)
Faith is assent to propositions “…upon the credit of the proposer, as coming from God, in some extraordinary way of communication.” Faith concerns revelation, undiscoverable by reason. Locke distinguishes original revelation (God to a person) and traditional revelation (original revelation “…delivered over to others in Words, and the ordinary ways of our conveying our Conceptions one to another” (IV.18.3, N: 690).
Locke notes some things are discoverable by both reason and revelation (Euclid’s geometry). In such cases, faith is less useful. Traditional revelation is less certain than idea agreement/disagreement contemplation. Revelation about facts is less certain than direct experience. Revelation cannot contradict known truths; contradiction undermines all faculties’ trustworthiness. Revelation’s domain is where reason fails:
…that Part of the Angels rebelled against GOD, and thereby lost their first happy state: and that the dead shall rise, and live again: These and the like, being Beyond the Discovery of Reason, are purely matters of Faith; with which Reason has nothing to do. (IV.18.8, N: 694)
Reason still plays a vital role regarding revelation:
Because the Mind, not being certain of the Truth of that it evidently does not know, but only yielding to the Probability that appears to it, is bound to give up its assent to such Testimony, which, it is satisfied, comes from one who cannot err, and will not deceive. But yet, it still belongs to Reason, to judge of the truth of its being a Revelation, and of the significance of the Words, wherein it is delivered. (IV.18.8, N: 694)
Reason judges revelation genuineness using probability canons. Without clear faith/reason boundaries, religion becomes unreasonable, leading to “extravagant Opinions and Ceremonies…” (IV.18.11, N: 696).
Accepting revelation without rational judgment leads to enthusiasm, a third assent principle alongside reason and revelation. Enthusiasm is unfounded confidence in divine favor or communication, negating reason’s role in judging genuineness. Ungenuine communications are “ungrounded Fancies of a Man’s own Brain” (IV.19.2, N: 698), characteristic of Protestant extremists since the Civil War. Locke strongly rejects enthusiasm, violating the principle of proportionate assent to evidence, a catastrophic abandonment. Locke emphasizes reason’s role in truth-seeking in The Conduct of the Understanding and The Reasonableness of Christianity. He critiques enthusiasts who abandon reason for faith:
…he that takes away Reason to make way for Revelation, puts out the Light of both, and does much what the same, as if he would perswade a Man to put out his eyes, the better to receive the remote Light of an invisible Star by a Telescope. (IV.19.4, N: 698)
Enthusiasts avoid reasoning’s labor, claiming immediate revelation, leading to “odd Opinions and extravagant actions,” warning against this principle. Locke firmly rejects inward persuasion unjudged by reason as legitimate. Locke’s emphasis on reason, balanced with faith and critical of enthusiasm, is a core element of john locke ideas about belief and knowledge.
3. Locke on Education: Shaping Minds for Liberty and Reason
Locke’s educational works, Some Thoughts Concerning Education and Conduct of the Understanding, bridge An Essay Concerning Human Understanding and his political writings, highlighting the practical application of john locke ideas. Grant and Tarcov note:
The idea of liberty, so crucial to all of Locke’s writings on politics and education, is traced in the Essay to reflection on the power of the mind over one’s own actions, especially the power to suspend actions in the pursuit of the satisfaction of one’s own desires until after a full consideration of their objects (II.21.47, N: 51–52). The Essay thus shows how the independence of mind pursued in the Conduct is possible. (G&T 1996: xvi)
Some Thoughts Concerning Education, published in 1693, compiles Locke’s advice to Edward Clarke on educating his son and daughters since 1684. While revising Essay’s fourth edition, Locke began “The Conduct of the Understanding,” intended as a chapter but left unfinished. Published posthumously in 1706, the Conduct and Thoughts complement each other. Thoughts focuses on parental child education; Conduct on adult self-education (G&T 1996: vii), though tensions illustrate liberal society paradoxes. Thoughts is tailored to educating English gentry children in the late 17th century, more time-and-place specific than Conduct. Yet, its emphasis on virtues like:
justice as respect for the rights of others, civility, liberality, humanity, self-denial, industry, thrift, courage, truthfulness, and a willingness to question prejudice, authority and the biases of one’s own self-interest
represents qualities essential for citizens in a liberal society (G&T 1996: xiii). These educational principles are rooted in john locke ideas about reason and individual autonomy.
Locke’s Thoughts embodies “the discovery of the child” of the era. Medieval children were often seen as miniature adults, their ages and individual needs largely ignored. Locke viewed children as developing human beings requiring parental nurturing of rationality. He urged parents to spend time with children, tailor education to individual character, develop sound bodies and character, and prioritize play over rote learning and punishment. He advocated language learning through conversation before grammar rules and suggested learning a manual trade.
Advocating education that fostered independent thinking, Locke prepared individuals for self-governance and civic participation. Conduct reveals connections between reason, freedom, and morality. Reason, free from bias, intolerance, passion, and questioning authority, leads to fair judgment and action. Cultivating reason is a moral responsibility to avoid passion and prejudice (G&T 1996: xii). This is, in Tarcov’s term, Locke’s “education for liberty,” directly reflecting john locke ideas on individual freedom and responsible citizenship.
4. John Locke’s Political Philosophy: The Two Treatises of Government
Lord Shaftesbury’s dismissal as Lord Chancellor in 1673 marked his shift to opposition leadership, heading the Country Party. In 1679, the Exclusion Crisis centered on preventing James, Duke of York, from succeeding Charles II due to James’s Catholicism. The Country Party, with a Commons majority, passed an Exclusion Bill, but it failed in the Lords due to royal opposition. Parliamentary efforts failed, and some Country Party leaders planned armed rebellion. The political context of the Exclusion Crisis is crucial for understanding john locke ideas on government and resistance.
Two Treatises of Government, published in 1689 after the Glorious Revolution, initially appeared to justify that event. However, now it’s understood Two Treatises was written during the Exclusion Crisis around 1681, possibly to justify a planned Country Party uprising.
A rebellion to exclude James faced obstacles. Anglican gentry support was needed, but Anglican doctrine emphasized obedience to superiors, allowing passive resistance to unlawful commands, but not active rebellion (Dunn, 1968, 48). By 1679, royal opposition to exclusion was clear, making support for exclusion “explicit and self-conscious resistance to the sovereign.” Passive resistance was insufficient. Yet, royal policy “outraged their deepest religious prejudices and stimulated their most obscure emotional anxieties.” The gentry were conflicted. Dunn notes: “To exert influence upon their choice it was above all necessary to present a more coherent ordering of their values, to show that the political tradition within which the dissenters saw their conduct was not necessarily empirically absurd or socially subversive. The gentry had to be persuaded that there could be reason for rebellion which could make it neither blasphemous or suicidal.” (Dunn, 1968, 49). To achieve this, Locke targeted Sir Robert Filmer (c 1588–1653), a staunch defender of divine right monarchy whose Patriarcha (published 1680) was the most complete exposition of the view Locke opposed. Filmer argued for inherent servitude to authoritarian family, social hierarchy, and sovereign, constrained only by God, making resistance “vicious, blasphemous and intellectually absurd.” Locke needed to refute Filmer, “rescue the contractarian account of political obligation from the criticism of impiety and absurdity,” and “restore to the Anglican gentry a coherent basis for moral autonomy or a practical initiative in the field of politics.” (Dunn, 1968, 50). This political objective shaped the arguments and aims of john locke ideas in Two Treatises.
The First Treatise of Government polemically refutes Filmer’s theological defense of patriarchal divine right monarchy. Locke attacks Filmer’s premise that men are not “naturally free,” the “ground” for Filmer’s claim that all “legitimate” government is “absolute monarchy,” with kings descended from Adam and subjects naturally slaves. Locke argues neither scripture nor reason supports Filmer’s claims, dissecting key Biblical passages.
The Second Treatise of Government presents Locke’s positive theory of government while continuing to counter Filmer’s claim of monarchs’ absolute power. Locke argues Filmer’s view is incoherent, leading to governments based on force. Locke offers an alternative account of government origin “lest men fall into the dangerous belief that all government in the world is merely the product of force and violence” (Treatises II,1,4). Locke employs natural rights theory and social contract theory, common in 17th-18th century political philosophy. Natural rights are inherent human rights pre-government. Social contract theory posits government arises from agreement, people transferring rights to government while retaining others. Locke’s radical natural rights theory influenced American and French Revolutions. These theories are central to john locke ideas on legitimate government.
Locke refutes Filmer by showing Filmer conflates limited powers (over wives, children, servants, slaves, commonwealth subjects), falsely presenting kings as having absolute power. Properly distinguishing and limiting these powers clarifies monarchs lack legitimate absolute power.
4.1 The Second Treatise: State of Nature and Natural Rights
A key goal in Locke’s Second Treatise is defining legitimate government to distinguish it from illegitimate forms, clarifying grounds for legitimate revolution, core tenets of john locke ideas. Examining existing government complexity makes this difficult. Locke’s strategy is to consider life without civil government – the state of nature, simpler and potentially easier to understand, to then deduce government’s proper role, following Hobbes and others. Chapter 1 of Second Treatise defines political power:
Political power, then, I take to be a right of making laws with penalties of death, and consequently all less penalties, for the regulating and preserving of property, and of employing the force of the community, in the execution of such laws, and in the defence of the common-wealth from foreign injury; and all this only for the public good. (Treatises, II, 1,3)
Chapter 2 describes the state of nature, lacking government with real political power. The state of nature isn’t necessarily government-less, but lacking full political power. It can include no government, illegitimate government, or legitimate government with limited power. (See state of nature in Locke’s political philosophy entry).
The state of nature, before government, is politically equal, no natural superior/inferior. From equality flows mutual love, reciprocal duties, justice, and charity. Did such a state ever exist? Hobbes and Locke likely answered yes. Whenever people haven’t agreed on common political authority, they remain in the state of nature. It’s analogous to being naturally single until married. Locke suggests the state of nature exists in “inland, vacant places of America” (Second Treatise V. 36) and in relations between peoples. State historical development may have also passed through a state of nature. Alternatively, the state of nature might be a theoretical construct, defining government’s proper function. Even if ahistorical, it remains analytically useful. For Locke, it is likely both. This concept of the state of nature is foundational to john locke ideas on political legitimacy.
4.2 Human Nature and God’s Purpose: Foundation of Natural Rights
According to Locke, God created humanity, making us God’s property. Our creator’s primary purpose for us as a species and individuals is survival. A wise, omnipotent God, creating and placing humans in the world:
…by his order and about his business, they are his property whose workmanship they are, made to last during his, not one another’s pleasure: and being furnished with like faculties, sharing all in one community of nature, there cannot be supposed any subordination among us, that may authorize us to destroy one another, as if we were made for one another’s uses, as the inferior ranks of creatures are for our’s. (Treatises II,2,6)
Thus, “he has no liberty to destroy himself, or so much as any creature in his possession, yet when some nobler use than its bare possession calls for it” (Treatises II.2.6). Murder and suicide violate divine purpose.
If survival is the goal, what means are necessary? Locke identifies life, liberty, health, and property. Given God sets survival as the end, Locke argues we have a right to the means, hence rights to life, liberty, health, and property – natural rights, pre-government, equally held by all. These natural rights are cornerstones of john locke ideas on individual liberty and limited government.
There is also a law of nature – the Golden Rule, interpreted through natural rights. Locke writes:
The state of nature has a law of nature to govern it, which obliges everyone: and reason which is that law, teaches all mankind who will but consult it, that being all equal and independent, no one ought to harm another in his life, health, liberty or possessions…. (Treatises II.2.6)
Locke states natural law is revealed by reason, commanding what’s best for us. Otherwise, it would be disobeyed. Reason reveals natural law by reflecting on self and others’ best interests, given survival and natural equality. (See natural law in Locke’s political philosophy entry).
Locke’s state of nature isn’t utopian, but an analytical tool to explain civil government necessity and legitimate function. Life in the state of nature has problems. Natural law, like civil law, can be violated. No police, prosecutors, or judges exist in the state of nature (governmental roles). Victims must enforce natural law, and judge on their own behalf. We can assist each other, intervening even when not directly threatened to enforce natural law – justifying legitimate rebellion. However, wronged individuals are likely to judge crimes more severely than impartial judges, leading to miscarriages of justice, a primary problem with the state of nature. This analysis of the state of nature motivates john locke ideas on the necessity of civil government.
4.3 War, Slavery, and Property: Key Concepts in Locke’s Political Thought
In Chapters 3 and 4, Locke defines states of war and slavery. The state of war is when someone has a “sedate and settled intention” to violate another’s right to life (and thus all rights), becoming an unjust aggressor in a state of war with the intended victim. This is not the normal state of nature relationship enjoined by natural law, love for fellow humans. Locke distinguishes himself from Hobbes, who equated state of nature and state of war. For Locke, state of nature is typically Golden Rule-governed; war arises from rights violations. Locke’s war theory always has an innocent victim and unjust aggressor.
Slavery is being under absolute or arbitrary power. Legitimate slavery arises only from being an unjust aggressor defeated in war. The just victor can choose to kill or enslave the aggressor. Locke defines slavery as a continuation of the state of war between conqueror and captive, where the conqueror delays killing the captive, using them instead. Slavery ends if conqueror and captive contract for obedience and limited power, becoming a master-servant relationship with limited master power. Slavery ceases because “no man, can, by agreement pass over to another that which he hath not in himself, a power over his own life” (Treatises II.4.24). Legitimate slavery defines despotic power limits, illuminating illegitimate slavery – absolute power without just cause, which Locke argues absolute monarchs seek to impose, explaining legitimate slavery’s narrow definition. This chapter on slavery is crucial to Locke’s argument against Filmer, not easily dispensable. However, Locke might have had other purposes, or reasons, for discussing slavery.
Debate exists whether Locke’s slavery theory in Second Treatise was intended to justify Afro-American slavery, given his trade and colonial government involvement. If so, his philosophy wouldn’t contradict his actions as investor/administrator. However, strong objections exist. Justifying Afro-American slavery would require a far broader legitimate slavery definition than Locke provides. Some suggest Locke’s “just war” is vaguely manipulable to justify Afro-American slavery, but this is also unlikely. In “Of Conquest,” Locke explicitly limits conqueror power, ensuring his conquest and slavery theory condemns Afro-American slavery in 17th-19th centuries. Nonetheless, debate continues, partly related to Locke’s role in Fundamental Constitutions of the Carolinas. David Armitage argues Locke revised Fundamental Constitutions while writing Two Treatises, with the provision “Every Freeman of the Carolinas has absolute power and authority over his negro slaves” unchanged. Thomas Wilson’s The Ashley Cooper Plan (2016) details Ashley Cooper’s Carolina vision thwarted by Barbadian slave owners transforming it into a slave society. L.H. Roper’s Conceiving Carolina (2004) focuses on Indian slave trade conflicts. James Farr’s “Locke, Natural Law and New World Slavery” (2008) argues Locke’s slavery theory targeted English absolutism, not Afro-American slavery, but notes Locke’s slavery involvement damaged his liberty champion reputation. Roger Woolhouse notes “a glaring contradiction between his theories and Afro-American slavery” (Woolhouse 2007: 187). These debates highlight the complexities and potential contradictions within john locke ideas regarding liberty and slavery.
Debate also exists about Locke’s target in his slavery and absolutism critique. Johan Olsthoorn and Laurens van Apeldoorn (2020) argue Locke’s rejection of consensual absolute rule has limited force against Grotius and Puffendorf, who defended absolutism and colonial slavery. Felis Waldmann refutes several of their claims, arguing Locke’s target was Filmer, accurately representing Royalist views in the 1670s-80s, not a straw man. Waldmann suggests Locke’s self-enslavement argument may target Hobbes, who endorsed both self-enslavement and royal dominium. William Uzgalis argues Locke has two slavery theories: legitimate and illegitimate. Locke shares with Filmer dominium slavery allowing master killing/maiming, but neither theory originates with Filmer. If Locke is correct about royal absolutism, and given slave trade/colonial slavery practices, both fall under illegitimate slavery. Grotius, Puffendorf, and Hobbes lack explicit illegitimate slavery theories. Uzgalis notes Grotius and Puffendorf offered arguments Locke could have used to justify slave trade/colonial slavery, but Locke rejected them, weakening his absolutism critique. This suggests Locke was crafting an alternative theory, not arguing against competitors, possibly except Hobbes.
Holly Brewer’s “Slavery, Sovereignty, and ‘Inheritable Blood’” (2017) argues Stuart kings, Charles II and James, Duke of York, promoted Royal Africa Company, slave trade, and colonial slavery for royal revenue. James was Royal Africa Company Governor and Admiral, Shaftesbury sub-governor, Locke assistant. James used the fleet to capture Dutch African forts for the Royal Africa Company. Stuarts minted guinea coins to celebrate. James continued as Governor after becoming King. Brewer stresses connections between domestic absolutism and colonial slavery, arguing slavery’s spread was English imperial policy. She claims Locke, in William III’s Board of Trade, sought to undo Stuart slavery policies. These debates highlight the ongoing scholarly re-evaluation of john locke ideas in light of historical context and his involvement with slavery.
Chapter 5, “Of Property,” is among the most famous and influential in Second Treatise, with interpretations highly debated. It describes state of nature evolution leading to civil government, explaining private property origins and the transition to civil government. (See property in Locke’s political philosophy entry). Locke begins by noting God gave Earth to humanity in common, raising the question of private property’s origin. Locke finds this a “serious difficulty.” He notes we should use Earth “for the best advantage of life and convenience” (Treatises II.5.25). Private property doesn’t arise from universal consent; waiting for everyone’s agreement to eat berries would lead to starvation. Locke argues we own ourselves, our labor and handiwork are our property. Picking acorns or berries makes them the picker’s property. Daniel Russell argues Locke’s “labor” is goal-directed activity converting potential resources into actual resources (Russell 2004), connecting to our natural law obligation to self-preservation and assisting others.
One might assume unlimited acquisition, but this is not the case. Locke introduces qualifications, initially waste.
As much as anyone can make use of to any advantage of life before it spoils, so much by his labor he may fix a property in; whatever is beyond this, is more than his share, and belongs to others. (Treatises II.5.31)
Early populations were small, resources vast, living within reason’s bounds limited property disputes. A single person could only use a small fraction of available resources.
Locke initially discusses hunting and gathering, and reason’s limits on property. He then shifts to agriculture, land ownership, and limitations. We see state of nature evolution from hunter-gatherer to farming society. Again, labor limits enclosed land – only what one can work. Another qualification is introduced:
Nor was this appropriation of any parcel of land, by improving it, any prejudice to any other man, since there was still enough, and as good left; and more than the as yet unprovided could use. So that, in effect, there was never the less for others because of his inclosure for himself: for he that leaves as much as another can make use of, does as good as take nothing at all. No body could consider himself injured by the drinking of another man, though he took a good draught, who had a whole river of the same water left to quench his thirst: and the case of land and water, where there is enough, is perfectly the same. (Treatises II.5.33)
The next state of nature evolution is money introduction. Locke notes:
… before the desire of having more than one needed had altered the intrinsic value of things, which depends only on their usefulness to the life of man; or had agreed, that a little piece of yellow metal, which would keep without wasting or decay, should be worth a great piece of flesh, or a whole heap of corn; though men had a right to appropriate by their labor, each one of himself, as much of the things of nature, as he could use; yet this could not be much, nor to the prejudice of others, where the same plenty was left to those who would use the same industry. (Treatises II.5.37)
Before money, economic equality was imposed by reason and barter. Needs and conveniences were primary. Necessities are perishable – berries, venison. Bartering berries for longer-lasting nuts was reasonable. Locke says:
…if he would give his nuts for a piece of metal, pleased with its color, or exchange his sheep for shells, or wool for a sparkling pebble or diamond, and keep those by him all his life, he invaded not the right of others, he might heap up as much of these durable things as he pleased; the exceeding of the bounds of his property not lying in the largeness of his possessions, but the perishing of anything uselessly in it. (Treatises II.5.146)
Money allows differential property increase, economic inequality. Without money, exceeding earlier economic equality is pointless. Money economies allow vastly different proportions based on industry.
This partage of things in an inequality of private possessions, men have made practicable out of the bounds of society, and without compact, only by putting a value on gold and silver, and tacitly agreeing to the use of money: for in governments, the laws regulate the rights of property, and the possession of land is determined by positive constitutions. (Treatises II.5.50)
Money-induced inequality multiplies quarrels and natural law violations, prompting civil government creation. What happens to property acquisition qualifications after money? C.B. Macpherson argues in Possessive Individualism qualifications are dropped, allowing unlimited private property acquisition. This is debated. Non-spoilage qualification is met by money’s durability. Other qualifications may become irrelevant through civil society property conventions. Did Locke approve of these changes? Macpherson sees Locke as proto-capitalist, advocating unlimited wealth acquisition. James Tully, in A Discourse of Property, sees Locke as critical of self-interest, viewing money-induced inequality and value changes as humanity’s fall. This interpretive divide is a major scholarly debate. Second Treatise is ambiguous. Locke’s Some Thoughts Concerning Education notes:
Covetousness and the desire to having in our possession and our dominion more than we have need of, being the root of all evil, should be early and carefully weeded out and the contrary quality of being ready to impart to others inculcated. (G&T 1996: 81)
4.5 Social Contract Theory: Consent as the Basis of Legitimate Government
Social contract theory flourished in the 17th and 18th centuries. Why is Locke a social contract theorist? Was it simply a prevailing idea he adopted? Locke’s project strongly pushes him towards social contract theory. Governments might originate in force, without agreement. But Locke would undermine his central distinction between legitimate and illegitimate government if legitimate government could arise from force. Locke says he must offer an alternative to the view
that all government in the world is merely the product of force and violence, and that men live together by no other rules than that of the beasts, where the strongest carries it … . (Treatises II, 1, 4)
While admitting some governments arise through force, legitimate government cannot. Legitimate government is instituted by the explicit consent of the governed. (See consent in Locke’s political philosophy entry). Those agreeing transfer their natural law enforcement and self-judgment rights to government, legitimizing government justice systems.
Ruth Grant argues government establishment is a two-step process. Universal consent forms a political community, binding and irrevocable. Grant writes: “Having established that the membership in a community entails the obligation to abide by the will of the community, the question remains: Who rules?” (1987: 114–115). Majority rule answers this. Universal consent establishes community; majority consent determines rulers. Grant writes:
Locke’s argument for the right of the majority is the theoretical ground for the distinction between duty to society and duty to government, the distinction that permits an argument for resistance without anarchy. When the designated government dissolves, men remain obligated to society acting through majority rule. (1987: 119)
Majority can choose monarchy, oligarchy, or democracy. Social contract isn’t inherently democratic. However, any government must perform legitimate civil government functions, essential to john locke ideas on political legitimacy.
4.6 The Function of Civil Government: Protecting Rights and the Public Good
Locke explains legitimate government function and distinguishes it from illegitimate government. Legitimate government aims to preserve citizens’ rights to life, liberty, health, and property, prosecute rights violators, and pursue public good, even if conflicting with individual rights. It provides an impartial judge absent in the state of nature, a primary benefit of civil society. Illegitimate government fails to protect rights, claiming despotic power over subjects. Locke, countering Filmer equating patriarchal and political power as despotic, distinguishes these powers in Chapter 15 “Of Paternal, Political and Despotic Power Considered Together”:
THOUGH I have had occasion to speak of these before, yet the great mistakes of late about government, having as I suppose arisen from confounding these distinct powers one with another, it may not be amiss, to consider them together.
Chapters 6 and 7 define paternal and political power respectively. Paternal power is limited to children’s minority. Political power, derived from individual right transfer to enforce natural law, includes the right to kill for citizen rights and public good. Legitimate despotic power involves the right to take life, liberty, health, and property without just cause – a concept Locke uses to critique absolute monarchy, a central theme in john locke ideas on limited government.
4.7 Rebellion and Regicide: Legitimate Resistance to Tyranny
At Second Treatise’s end, Locke addresses illegitimate government and legitimate rebellion and regicide. Written during the Exclusion Crisis, the book may have justified insurrection and regicide against the King and his brother. Legitimate revolution argument stems from distinguishing legitimate and illegitimate government. Legitimate government protects citizens’ rights to life, health, liberty, property, deserving obedience. Illegitimate government systematically violates natural rights, seeking illegitimate slavery, entering a state of nature and war with subjects. The magistrate/king becomes a dangerous “beast of prey” operating on “might makes right.” Rebellion and killing such a beast become legitimate. Locke justifies rebellion and regicide under specific conditions, potentially justifying the Rye House Plot had it succeeded. Even if not Locke’s intention, it served that purpose. This justification of resistance against tyranny is a powerful and enduring aspect of john locke ideas.
5. Locke and Religious Toleration: Separating Church and State
Religious toleration was widely debated in 17th-century Europe due to pervasive religious intolerance and violence. The Reformation split Europe, causing civil wars and religious persecutions. John Marshall notes the 1680s as a peak decade for persecution. The Dutch Republic, where Locke was exiled, was founded as a secular state allowing religious differences, reacting to Catholic persecution of Protestants. However, Calvinist dominance led to persecution of dissenters like Remonstrants. Yet, the Dutch Republic remained Europe’s most tolerant nation. France’s religious conflict was temporarily eased by the Edict of Nantes, but Louis XIV revoked it in 1685, persecuting Huguenots. England also experienced 17th-century religious conflict, contributing to the Civil War and Anglican Church abolition during the Protectorate. Restoration-era Anglican laws repressed Catholics and Protestant dissenters. Religious conflict and persecution profoundly shaped john locke ideas on toleration.
Comprehension and toleration were discussed strategies in England to reduce religious conflict. Comprehension aimed to minimize Anglican doctrine and practices to include most dissenters. Toleration meant lack of state persecution for those remaining outside. Neither strategy progressed much during the Restoration.
After fleeing to Holland, Locke joined a group advocating religious toleration, including Benjamin Furly, Pierre Bayle, Dutch theologians, and others. They debated religious intolerance arguments, advocating toleration for Protestants, dissenters, Jews, Muslims, and Catholics. Locke even considered Catholic toleration (Walmsley and Waldmann 2019). They promoted free speech, civility, and politeness, calling themselves ‘Republic of Letters’ or ‘commonwealth of learning.’
Locke’s religious views are complex. Religion, especially Christianity, deeply influenced his philosophy. His family was Puritan, but he avoided Anglican priesthood at Oxford, claiming Anglicanism until death. Some see him as Latitudinarian, advocating reasonable Christianity acceptable to dissenters. Others see him as neither orthodox Anglican nor Latitudinarian. Locke facilitated Newton’s anti-Trinitarian tract publication, suggesting Locke was Arian or Unitarian, rejecting Trinity doctrine. His Letter on Toleration advocates Church-State separation, seemingly not a state religion advocate. The Reasonableness of Christianity argues for Christianity’s basic doctrines being few and reason-compatible, possibly making him Latitudinarian. However, Ashcraft argues Anglican comprehension meant dissent abandonment. Latitudinarians might be “the acceptable face of the persecution of religious dissent” (Ashcraft 1992: 155). While Latitudinarian friends existed, The Reasonableness of Christianity could be dissenting “rational theology.” These complex religious influences are essential to understanding john locke ideas on toleration.
Locke considered religious toleration since 1659, with views evolving. Early 1660s, likely orthodox Anglican. He and Shaftesbury instituted religious toleration in Fundamental Constitutions of the Carolinas (1669). He wrote Epistola de Tolerantia (1685) in Holland, witnessing Huguenot refugees. Holland itself, while tolerant, had Calvinist theocracy issues. Locke’s Letter offers principled religious toleration, mixed with arguments specific to Christians, sometimes Protestants, excluding Catholics (agents of foreign power) and atheists (untrustworthy oaths). He defends toleration while using anti-Papist rhetoric against James II.
Locke’s toleration arguments connect to his civil government theory. Civil interests are life, liberty, health, property, magistrate’s concern, enforceable by force. Salvation is not a civil interest, outside magistrate’s legitimate concern. Locke adds right to choose one’s salvation path to natural rights. (See toleration in Locke’s political philosophy entry).
Locke argues state force to impose beliefs or practices is illegitimate. Force is ineffective for belief change. Forced religious profession is hypocritical:
A sweet religion, indeed, that obliges men to dissemble, and tell lies to both God and man, for the salvation of their souls! If the magistrate thinks to save men thus, he seems to understand little of the way of salvation; and if he does it not in order to save them, why is he so solicitous of the articles of faith as to enact them by a law? (Mendus 1991: 41)
State religious persecution is inappropriate. “Whatever is lawful in the commonwealth cannot be prohibited by the magistrate in the church.” Magistrates cannot prohibit bread and wine use, or even calf sacrifice.
If churches compete, which should have power? The true church, but every church believes itself true. No judge but God can decide. Religious knowledge skepticism is central to Locke’s toleration argument. Locke’s principled defense of religious toleration, with caveats, is a defining and influential aspect of john locke ideas.
Bibliography
(Please refer to the original article for the Bibliography)
