object of investigation being his own mind, "looking into it and seeing how it wrought ". He could find no innate ideas or principles in the mind. The primary source of all our knowledge is sensation or external perception, and reflection or internal perception; the former embraces the apprehension of external objects through the senses, while the latter comprises the apprehension of mental objects by internal or self-reflection, a subjective operation of thought. The different objects of external perception are variously related to objective reality. Thus extension, figure, motion, and other qualities of bodies belong to the external objects themselves; while colour, sound, and sensible qualities are only in ourselves, and not properly in the objects perceived, being signs not copies of changes which take place in external things. In the reception of simple ideas the mind is merely passive, it cannot refuse to have them, or blot them out, any more than a mirror can refuse to receive, alter, or obliterate the images reflected on it; all that man can do is to unite them together, classify them or separate them. By internal reflection we know the action of our thinking and willing faculties; while through sensation and reflection together, we obtain the feelings of pleasure and pain, the ideas of power, unity, existence, and others; but we have no clear idea of substance.56

56 The word idea has a wide meaning in Locke's Essay, as he uses it to denote whatever we apprehend, whether it be a mental modification of an external object, or a subjective thought, the perception or consciousness of feelings and passions; as when I form a mental picture or image of anything, or am conscious of a pleasant sound—when I see the moon or any external object, and when I remember any of these, again when I understand the meaning of right, of property, or any other abstract term-in all such cases, according to Locke, I am having ideas. Thus he employed the term idea in its most unrestricted universality. The theory of knowledge requires some definite word or words to indicate the dependence of what is known on the power of knowing. Descartes, Locke, and others, used the word idea in this relation, sometimes with perception, and at a later date, with impression. At present some use the term phenomenon, to express those aspects of existence of which we are conscious, rather than the words, ideas, perceptions, or impressions; others, again, use the word consciousness with a wide meaning, to express mental facts, modes, or states, in their relation to the knowing mind. But all terms thus used touch the prime assump

Locke devotes the First Book of his Essay to the refutation in detail of the doctrine of innate ideas. The argument that certain speculative and practical principles are universally accepted as true, he disputed, by showing that there was a mass of evidence against this alleged agreement, and that though it were otherwise, innate ideas would not be proved, as it might be shown that such agreement had arisen in other ways. He had little difficulty in proving that the principles of identity and of contradiction are unknown to children, and to all who are not specially educated: and, therefore, it could not be maintained that truths are inherent in the mind of which it has no consciousness and no knowledge. To say that an idea is imprinted on the mind, and yet at the same time to admit that the mind is ignorant of it, and never took notice of it, is to make this impression nothing. But it is true that the capacity to know is innate, though all actual knowledge is and must be acquired. And, therefore, those who adopt the theory of innate ideas should distinguish them from other ideas which are not innate; and thus they must hold that innate knowledge is from the first conscious knowledge, for to be in the understanding

tion of philosophy, namely, that the universe and all things which exist can become known to us only through our mental and self-conscious experience; and thus arises the problem of the relation of the human mind to the external world.

Now as already indicated in this chapter, there is a real difficulty involved in understanding and stating the exact relation between mind and matter; and the nature of the relation of the object known and the knowing mind is still unknown. All that we know is that knowledge consists in a certain relation of the object known to the knowing subject. Of mind in itself or matter in itself we know nothing; simply because we know only the qualities of our own faculties of knowledge, as relations to their objects, and we only know the qualities of their objects as relations to our minds: thus all qualities both of mind and of matter are only known to us as relations, we know nothing in itself. See Hamilton's Reid, note N., p. 965.

In Locke's Essay the word idea is used to recall the truth that external things become known to us through our presentative and representative conscious experience; but on the other side of his theory, ideas also represent qualities which exist external to our conscious mind; thus they are, as it were, "effects in us," produced by powers that are independent of us: that is, he assumes that the mind is merely passive in the reception of simple ideas.

means to be understood. If it be asserted that these principles are recognised and admitted by all men when they come to exercise their reason, this is not true or conclusive, whether in the sense that we know them deductively by the use of reason, or in the sense that we think them when we arrive at the use of reason, for we know many things before them. That the bitter is not sweet, that a rod and a cherry are not the same thing, are known by a child long before he understands and assents to the universal proposition that it is impossible for the same thing to be and not to be at the same moment. Practical principles stand upon the same footing as speculative ones, none of them being innate; and, moreover, they are not so clear or so universally received as the principle just indicated. If principles are innate, the ideas involved in them must also be innate. Now the most general principles contain the most abstract ideas, which are the furthest from the thoughts of children, and are unintelligible to them, and can only be clearly formed after they have attained some degree of attention and reflection. The ideas of identity and difference, possibility and impossibility, and others of a similar character, are not in the child's consciousness at birth; and they are farthest removed in the order of development from the sensations of hunger and thirst, heat and cold, pleasure and pain, which in reality are the earliest conscious experiences of a child.

Locke strongly maintained that the idea of God is not innate. And he attempted to prove that some tribes in the lowest stages of civilisation had no idea of God at all. He also pointed out the fact that the ideas and conceptions which the various tribes and nations of mankind have of God differed greatly.

Having thus cleared the ground, Locke, in his Second Book, proceeds to show whence the understanding receives its ideas. He asks, "Whence comes it by that vast store, which the busy and boundless fancy of man has painted on it, with an almost endless variety? Whence has it all the materials of reason

and knowledge? To this I answer in one word, from experience in that all our knowledge is founded, and from that it ultimately derives itself. Our observation employed either about external or sensible objects, or about the internal operations of our minds perceived and reflected on by ourselves, is that which supplies our understanding with all the materials of thinking. These two are the fountains of knowledge, from which all the ideas we have, or can naturally have, do spring." "57 Thus experience is twofold, external and internal, sensation and reflection, according as its object is the outer world of things, or the internal operations of our own minds. The senses in contact with external objects supply the mind with the elements and materials of ideas; and thus we attain the ideas of yellow, white, heat, cold, soft, hard, and all those called sensible qualities. Then when the mind attends and thinks on its own internal operations, the understanding thence attains another set of ideas such as, perception, thinking, doubting, believing, reasoning, knowing, willing, and all the different operations of our minds of which we are conscious and observe within ourselves.

When the first impression is made on his senses, man begins to have ideas. But before the first sensible impression, the mind no more thinks than it does afterwards in a deep and dreamless sleep. That the mind always thinks is as groundless an assertion as that all bodies are continually in motion.

Some of our ideas are simple, others are complex; and of the former class, some come into the mind by one sense only, some by more senses than one, others through reflection, while some come both by the senses and reflection. The simple ideas received by touch are heat, cold, solidity, roughness, hardness, smoothness, and many others; by the sense of sight, the ideas of light and colours; while the ideas which we receive by more than one sense, by sight and touch, are those of space, figure, rest, and motion. The simple ideas of reflection which the

57 Book II., Ch. I., Sect. 2.

mind acquires when it becomes conscious and observes its own operations, are mainly two, namely, perception or thinking, and volition or willing. But the other simple ideas acquired through all the channels of the senses and reflection, are those of pleasure and pain, power, existence, unity, and succession.

But the most of the ideas of sensation are no more like anything existing externally to ourselves, than words are like the ideas for which they stand, and which they serve to recall to the mind. The inseparable qualities of bodies themselves are those of bulk, figure, number, position, motion, and rest; and these he called the primary qualities of body. Now our ideas of these primary qualities of bodies are copies of these qualities; that is, they represent the thing mentally as it is in itself. But the secondary qualities of bodies affect us in a different way, they operate on the senses, and cause in us the sensations of colours, sounds, smells, and the like, which are not in the bodies themselves, but in our own minds. He further names a third class of qualities: these are the powers of some bodies, which, owing to the constitution of their primary qualities, make such changes in the bulk, figure, and motion of other bodies as cause them to operate upon our senses differently from what they did before; among these he instances the power of the sun to make wax white, and of fire to melt lead.58

Under the head of simple ideas acquired by reflection, he minutely investigated the faculties of perception, retention, discerning, compounding, abstracting, and other operations of the mind. The faculty of perception distinguishes man from animal and plant. The faculty of memory is the power of preserving ideas by continued contemplation, or by reviving them after their temporary absence from the mind, which is too limited to be conscious at the same time of many ideas. Memory is common to man and the lower animals. The power of abstraction is peculiar to man. By this generalising faculty the

ideas of single objects are separated from all accidental qualities,

58 Book II., Chaps. I.-VIII.