Locke I. General Notions Francis Bacon and Thomas Hobbes were not truly conscious of the phenomenalistic consequences of their theory of knowledge, which was based on empiricism. Both considered sensation as phenomenal presentations and also as representations of reality. Thus they still had something upon which to build an absolute metaphysics. With Locke gnosiological phenomenalism enters its critical phase.
By considering sensations merely as subjective presentations, Locke gives us a theory of knowledge of subjective data devoid of any relation with external objects. Hence Locke is the first to give us a logic for Empiricism, that is, for sensations considered as phenomena of knowledge. Such an attitude excludes any consistent metaphysics of objective reality. Locke, however, overlooking everything he has established in his solution to the problem of knowledge, gives us a metaphysics which is not greatly different from the scholastic. He even appeals to the familiar principles of Scholasticism, showing how difficult it is for man to withdraw from the philosophy of being. Berkeley, first, and then David Hume went all the way and reduced being to the status of a subjective phenomenon. In so doing, these two philosophers merely drew the logical conclusions of the gnosiological phenomenalism proposed by John Locke.
II. Life and Works John Locke was born in 1632 at Wrington, Somersetshire, England. He studied philosophy and the natural sciences at Oxford, and received his doctorate in medicine. Having entered into the graces of Lord Ashley, who later became the Earl of Shaftesbury, Locke held several political offices. Thus he had the opportunity to visit France, where he made the acquaintance of the most representative men of culture. In 1683 he went into exile in Holland; there he participated in the political movement that placed William of Orange upon the throne of England.
After the accession of William of Orange, he returned to England, retired to private life, and dedicated himself to his studies. He died in 1704. Locke is a representative of the English culture of his time. With a mind open to the most varied problems, Locke was a philosopher, a doctor of medicine, and educator, a politician and a man of action. Locke’s principal works, in chronological order, are: Treatises on Government; Essay Concerning Human Understanding (his masterpiece); Thoughts on Education.
III. Epistemology: Origin of Knowledge Descartes had admitted that some some ideas are innate in the intellect. Locke dedicated the first book of his Essay Concerning Human Understanding to a refutation of Descartes’ innatism. If we had innate ideas, says Locke, we would be conscious of having them. But it is an undeniable fact that children, savages, the unlearned, are not conscious of having innate ideas; they acquire knowledge during the course of a lifetime. It is impossible that anyone should have knowledge of something of which he is not conscious. Furthermore, experience teaches that certain moral principles and the notion of God, far from being innate, vary with different people and at different times.
Hence there exists no innate idea; our intellect, at the first moment of its being, is a tabula rasa, a clean sheet of paper on which nothing has yet been written. All impressions we later find thereon (which for Locke are ideas) come from experience. Locke’s ideas are not to be confused with Aristotle ideas, but are to be taken in the sense of representations, or better, of presentations. Locke explains that experience is twofold: external and internal. External experience, called sensation, gives us ideas of supposed external objects, such as color, sound, extension, motion.
etc. Locke says supposed objects, since their existence has not been proved. (In a theory of knowledge limited to the experience of mental content, such as that of Locke, it is utterly impossible to prove the actual existence of these supposed objects.) Internal experience, called reflection, makes us understand the operation of the spirit on the objects of sensation, such as knowing, doubting, believing and so forth. In regard to the ideas furnished by sensation, it is necessary to distinguish the primary qualities (solidity, extension, figure, number, motion, etc.), which are objective, from the secondary qualities (color, sounds, etc.), which are subjective in their effect and objective in their cause. In other words the secondary qualities are powers for producing various sensations in us.
(Essay, II, i and viii passim.) For Locke, sensation and reflection are classified as simple and complex, according to whether they are irreducible elements, such as whiteness, rotundity, or reducible to more simple elements. Thus the idea of an apple is complex because it is a combination of the simple ideas of color, rotundity, taste, and so forth. The spirit is passive as regards simple ideas; no one can have the idea of sound, for example, if it is not furnished to him. On the contrary, the spirit is active concerning complex ideas because it can reduce them to simple elements and can construct new complex ideas from these elements. (Essay, II, ii, 1-30.) Locke distinguishes three classes of complex ideas: 1. Ideas of substance, representing a constant or stable collection of simple ideas related to a mysterious substratum which is their unifying center; 2.
Ideas of mode, resulting from the combination by the intellect of several ideas, in such a manner as to form not a thing in itself but a property or mode of an existing thing — for example, a triangle, gratitude; 3. Ideas of relationship, arising from the comparison of one idea with another, such as temporal and spatial relationships, or the relationship of cause. In addition to complex ideas, there are also general ideas, which result from the isolation of a simple idea from a complex one — for example, whiteness — and from the universalization of the idea in so far as it represents the characteristics common to several similar sensations. General ideas hence are abstract ideas, and are useful for signifying a collection of common sensations (nominalism). (Essay, II, xii, 1-8.) IV. Epistemology: Value of Knowledge Having thus analyzed and described the various contents of consciousness, man has to determine what he knows through these ideas — that is, what is their logical and metaphysical value.
Logical Value of Ideas. By logical value we mean the perception of the agreement or disagreement between two ideas when they are compared to one another. This perception of agreement or disagreement, according to Locke, can be either intuitive or demonstrative. In the first case the relationship between two ideas is immediately seen by the spirit, as in the example Two plus two equals four, or A triangle is not a square. In the second case, the mind must have recourse to intermediate ideas in order to perceive the relationship of agreement or disagreement.
Truths of this kind are obtained through demonstration. Being empirical concepts, they are inferior in value to intuitive truths. Thus, to know the existence of external objects man must have recourse to the intermediate idea of the passivity of thought — for it is the external objects that are acting upon his mind and producing in it external sensations. Metaphysical Value of Ideas. Analysis and the exposition of the relationship between different ideas lead to logical truths, that is, …