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Locke, John


British philosopher, generally regarded as the founder of empiricism; b. Wrington, near Bristol, Aug. 29, 1632; d. Oates, Essex, Oct. 28, 1704. Locke was educated at home until he attended Westminster school in 1646. He later went to Oxford, where he received the B.A. and M.A. degrees. At Oxford he read philosophy, became interested in physics and chemistry, and took his medical degree (1674); he never practiced medicine, however, turning his attention to public affairs instead. In 1665 he took a position as secretary to Sir Walter Vane and two years later entered the service of Lord Ashley, afterward the first Earl of Shaftesbury. Because of his involvement in political intrigue with Shaftesbury, Locke was forced to flee to Holland. He did not return until 1688, when William of Orange became king of England.

Locke's is a plain historical method by which he hoped to achieve an empirical analysis of knowledge based on experience and devoid of the pretensions of rationalism. He applies this analysis to ethics, politics, and religion.

Theory of Knowledge. As his main work, The Essay concerning Human Understanding (1690), indicates, Locke is no radical empiricist. The Essay is characterized by a plain, commonsense approach and its rational reflection on ordinary experience. In it, Locke rejects all innate ideas and insists that the sources of knowledge are experiential, viz., sensation and reflection. From sensation the mind derives ideas, while from reflection it becomes aware of such internal operations as thinking, willing, and desiring. Locke divides ideas into two different classes: simple and complex. Simple ideas are produced in the mind in various ways: (1) some are formed by an external object acting on one or more of the external senses, for example, the idea of hardness or sweetness; (2) others are caused by the internal actions of thinking and willing; (3) still others are produced by a combination of internal and external activity, such as the ideas of pain and pleasure. Complex ideas are combinations of simple ideas, and of these Locke lists three different classes: (1) ideas of modes, which are collections of simple ideas conceived of as modifications of substance; (2) ideas of substances; and (3) ideas of relations.

Ideas and Understanding. Whatever the nature of the idea, simple or complex, it is the idea that the mind understands. Man knows ideas, and knowledge is nothing else but an apprehension of the agreement or disagreement of ideas (Essay, bk. 4, ch. 1). This conception leads Locke into an almost complete subjectivism, against which he struggles in vain throughout the various parts of the Essay. The agreement or disagreement of ideas can take various forms: (1) identity and diversity, (2) relation between ideas, (3) coexistence of ideas, and (4) ideas of real existence (Essay, bk. 4, ch. 3). It is in examining the different kinds of ideas composing knowledge that Locke discerns the meaning and structure of reality.

Cause of Ideas. Having rejected the doctrine of innate ideas, Locke is forced to posit something as the cause of simple ideas. Hence he argues that things or substances that affect man in certain ways must exist. Since what man knows is the effect on him, substance must remain an unknown that is supposed to exist as a substratum for the various qualities and powers through which the thing is able to act. Here, however, a distinction must be made. Since man experiences certain affections that are consistently the same in relation to all material things, such things must really possess these qualities. All bodies, for example, appear as solid, as having some shape and magnitude, and as being in motion or at rest. These are primary qualities and are real modifications of bodies. There are, however, other affections that differ from individual to individual, such as sweet and bitter, hot and cold. These subjective affections, corresponding to the sensations of the external senses traditionally affirmed color, taste, odor, touch, and soundLocke calls secondary qualities. The only objective references such qualities have are the powers bodies have to cause such affections in a sensing subject. From this viewpoint substance is merely a name given to a collection of secondary sense qualities. Gold, for example, means merely a combination of the simple ideas of yellow, hard, shiny, etc. This name is the nominal essence, as distinguished from the real essence, which is supposed to exist beneath the primary qualities and powers, but which can never be known (Essay, bk. 2, ch. 23; bk. 3, ch. 6).

Locke, however, always remains a realistif an inconsistent onebecause he never denies the existence of this unknown substratum. He holds, too, the reality of primary qualities and their real power to affect man. He also makes use of several so-called commonsense arguments to establish the reality of a material world distinct from the knowing subject. He refers to the idea of cause as an idea with a foundation in real existence, and he appeals to the real idea of fire as opposed to the imaginary idea of fire. Let one put his hand into a real fire, Locke notes, and he straightway understands the difference (Essay, bk. 4, ch. 11).

Divisions of Knowledge. Locke divides the mind's knowledge of ideas on the basis of degrees of intensity. First is intuitive knowledge, which is an immediate apprehension of the agreement or disagreement between ideas; e.g., the idea of bitter is not the same as that of yellow. Then there is knowledge of ideas attained through the mediation of other ideas apprehended intuitively; this is demonstrative knowledge, although Locke is careful to point out that intuition must accompany each step in the demonstrative process. Mathematical knowledge is of this sort. On the level of the natural sciences, however, Locke does not think that necessary connections can be established between ideas. He sees only a de facto connection in this area; hence, he does not regard the conclusions of the natural sciences as demonstrable, but only as enjoying high degrees of probability.

Existence of God. Under demonstrative knowledge Locke includes also the knowledge of God's existence. His proof begins with an intuition of one's own existence. Since nothing cannot produce something and since man is aware that he had a beginning, he must have been produced by something else. If there is not some eternal being, the problem simply regresses indefinitely. Therefore, something eternal must exist, and this is God. Furthermore, not only does God produce that which has a beginning, but He also produces it as the kind of being that it is. Again, there are created beings that have intelligence and the capacity to love. Hence, God must also be intelligent and loving and, therefore, a personal being.

Ethical Theory. Locke continues his empiricism in his ethical theory. For Locke, all moral ideas are grounded in experience, but these ideas can be clearly grasped and just as clearly related to one another. They can then serve as norms for judging the morality of activity. Moral good consists in the conformity of voluntary actions to these established norms. From this viewpoint Locke sees no reason why ethics cannot be as clear and certain a science as mathematics.

Norms are of different kinds, and Locke enumerates them as divine law, civil law, and the law of opinion or reputation. In relation to the divine law, actions are judged to be duties or sins. In relation to the civil law, actions are called innocent or criminal. In relation to the law of opinion, actions are judged as praiseworthy or blameful, depending on the manners or customs of the place. Since it is obvious that these laws can and do conflict with each other, Locke holds that the divine law must be the ultimate norm of moral activity. He maintains that this divine law can be known by human reason, and to this extent he seems to hold for the existence of a basic moral absolute, to which man has the obligation to conform.

Political Theory. In his political philosophy Locke attacks both the theory of the divine right of kings and of the nature of the state as understood by T. hobbes. According to Locke, the original state of nature was not a state of war and license but one of peace, in which natural rights and obligations prevailed. However, because such a situation could not adequately supply man's needs or protect him from abuses, he entered into a political state, by either explicit or tacit consent; such a state could then make laws for him, as the public good or society required. Hence, sovereignty resides in the people and is delegated by them to their authorities. For him, as for Hobbes, authority in the state is supreme; but, unlike Hobbes, Locke insists that governing authorities are bound by both civil and "natural law." Hence, such authority is validly exercised only as long as it respects the "common good." There is therefore an authority superior to civil authority.

One of the chief goods to be achieved in the state is the right to the acquisition of private property. Locke sees this right as founded in labor. The laborer, in working on the land or on some natural product, contributes something of himself and thus acquires a title to it. Such a right, however, is not unlimited; it is restricted to as much property as a man can reasonably put to use.

Approach to Religion. In his approach to religion Locke gives the impression of being a sincere Christian who sees no discrepancy between reason and Christianity. In bk. 4, ch. 17, of the Essay, Locke distinguishes truths according to reason, those above reason, and those contrary to reason. Christianity deals with truths that are above reason, and it is to these that the Christian makes an assent of faith. Such truths must be proposed by God for man's belief, and it is here that Locke encounters difficulty. How is one to know that God is really the author of such truths? Locke's answer refers to the outward signs that accompany them, i.e., miracles. But how is one to know that such signs are really miraculous? It seems that Locke must either settle for some sort of probability here or else have recourse to an intuition of the connection between a given sign and the proposition of faith that it is supposed to justify. In neither case is the solution satisfactory, since it makes faith in the first instance only a probable proposition or, in the second, makes reason itself the criterion of Christian faith. Locke's approach is at best naturalistic and at worst rationalistic, in the sense that it makes reason the ultimate criterion even of truths that are above reason (Essay, bk. 4, ch. 19).

Influence. Locke has had a lasting influence on modern philosophy. Berkeley's empirical idealism is a direct outgrowth of Locke's epistemology, as is Hume's later skepticism. Locke himself attempted to hold a commonsense middle position between these two extremes, but both Berkeley and Hume represent the logical consequences of the position. The systems of D. Hartley and J. S. mill are clearly indebted to Locke. And through Hume, the Kantian doctrines of the unknown thing-initself, the nature of substance, the intellectual categories reveal either Kant's acceptance of Locke or his attempt to overcome what he considered an extreme empiricism.

There is good reason to believe that Locke's theory of government influenced the founders of the American Constitution, and Thomas Jefferson especially. The American people were establishing a government after their successful Revolution, and Locke had sought to justify the Glorious Revolution in England. Some of Locke's idease.g., on natural rights, the rule of the majority, property rights, and the obligation of government to secure and preserve these rightsappear in the Constitution, at times exactly in Locke's phrasing. And 19th-century American laissez-faire individualism was rooted in the Lockean notion of natural rights, indirectly by way of constitutional interpretation.

In contemporary philosophy most systems of naturalism, logical positivism, and analytical philosophy are sympathetic to Locke. They generally accept his position on the object of knowledge, the nature of substance, the lack of innate ideas, and the nominalistic interpretation of the function of the idea.

Critique. The basic difficulty with Locke's experiential approach is the assumption from which it begins: what is known is only an affection of the knowing subject. This subjectivism puts Locke into a position where he is forced to prove the reality of an external world and God. He himself recognized the difficulty and strove in vain to overcome it. Berkeley showed him the impossibility of demonstrating the existence of material reality, and Kant made clear the inadequacy of his proof for the existence of God. Such a subjectivism had to end where it beganin the mind. The ease with which such an approach slips into a complete idealism and even into solipsism is only too apparent in the history of philosophy. Man's basic experience is of things, not of ideas. Any theory of knowledge denying that basic experience is bound to lead to the bankruptcy of all knowledge.

See Also: knowledge, theories of.

Bibliography: Works, 10 v. (rev. ed. London 1823); The Philosophical Works of John Locke, ed. j. a. st. john, 2 v. (London 1854); An Essay concerning Human Understanding, ed. a. c. fraser, 2 v. (Oxford 1894); The Reasonableness of Christianity, ed. i. j. ramsey (Stanford 1958); Two Treatises of Government, ed. t.i. cook (New York 1947); The Correspondence of John Locke and Edward Clarke, ed. b. rand (London 1927); Selections, ed. s. p. lamprecht (New York 1928). Literature. f. c. copleston, History of Philosophy (Westminster, Md. 1959) v.5. a. carlini, Enciclopedia filosofica, 4 v. (Venice-Rome 1957) 3:96112. p. k. king, The Life of John Locke, 2 v. (London 1830). r. i. aaron, John Locke (2d ed. Oxford 1955). d. j. o'connor, John Locke (Baltimore 1952). j. d. collins, A History of Modern European Philosophy (Milwaukee 1954).

[h. r. klocker]

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