as in bodily growth, so in mental growth, there is an assimila tion of like with like, or a process of integration. From the very first, along with the perception of difference, there has been also a perception of likeness. The clock-stroke, when first heard, is felt simply as an impression differing from others that precede and succeed it in the consciousness; but, when heard again, not only is there this recognition of difference, but it is perceived as like the clock-stroke which preceded it. This second impression is assimilated to the first, and, when a third arises, it also coalesces with the former like impressions. And so of all other sights, sounds, and touches. Under the influence of constant changes of impression, and a constant assimilation of like with like, there arise, at first vague, and then distinct unlikenesses among the feelings; that is, sights begin to be distinguished from sounds, and sounds from touches, while, at the same time, differences begin to be perceived among the impressions of each sense. In this way, the consciousness, at first homogeneous, grows into diversity, or becomes more heterogeneous, while its separated or differentiated parts are termed ideas.

Let us look into this a little more closely. When an infant opens its eyes for the first time upon the flame of a candle, for example, an image is formed, an impression produced, and there is a change of feeling. But the flame is not known, because there is as yet no idea. The trace left by the first impression is so faint that, when the light is removed, it is not remembered; that is, it has not yet become a mental possession. As the light, however, flashes into its eyes a great many times in a few weeks, each new impression is added to the trace of former impressions left in the nervous matter, and thus the impression deepens, until it becomes so strong

as to remain when the candle is withdrawn. The idea therefore grows by exactly the same process as a bone grows; that is, by the successive incorporation of like with like. By the integration of a long series of similar impressions, one portion of consciousness thus becomes differentiated from the rest, and there emerges the idea of the flame. Time and repetition are therefore the indispensable conditions of the process.1

Now, when the candle is brought, the child recognises or knows it; that is, it perceives it to be like the whole series of impressions of the candle-flame formerly experienced. It knows it because the impression produced agrees with the idea. In this way, by numerous repetitions of impressions, the child's first ideas arise; and, in this way, all objects are known. We know things, because, when we see, hear, touch, or taste them, the present impression spontaneously blends with like impressions before experienced. We know or recognise an external object not by the single impression it produces, but because that impression revives a whole train or group of previous discriminations that are like or related to

1 The single taste of sugar, by repetition, impresses the mind more and more, and, by this circumstance, becomes gradually easier to retain in idea. The smell of a rose, in like manner, after a thousand repetitions, comes much nearer to an independent ideal persistence than after twenty repetitions. So it is with all the senses, high and low. Apart altogether from the association of two or more distinct sensations, in a group or in a train, there is a fixing process going on with every individual sensation, rendering it more easy to retain when the original has passed away, and more vivid when by means of association it is afterwards reproduced. This is one great part of the education of the senses. The simplest impression that can be made of taste, smell, touch, hearing, sight, needs repetition in order to endure of its own accord; even in the most persistent sense the sense of seeing the impressions on the infant mind that do not stir a strong feeling will vanish as soon as the eye is turned some other way.-Professor Bain.

it;

while the number of those that are called up is the measure of our intelligence regarding it. If something is seen, heard, felt, or tasted, which links itself to no kindred idea, we say we do not know it;' if it partially agrees with an idea, or revives a few discriminations, we know something about it, and the completer the agreement the more perfect the knowledge.

6

As to know a thing is to perceive its differences from other things, and its likeness to other things, it is therefore strictly an act of classing. This is involved in every act of thought, for to recognise a thing is to classify its impression or idea with previous states of feeling. Classification, in all its aspects and applications, is but the putting together of things that are alike the grouping of objects by their resemblances; and as to know a thing is to know that it is this or that, to know what it is like and what it is unlike, we begin to classify as soon as we begin to think. When the child learns to know a tree, for example, he discriminates it from objects that differ from it, and identifies it with those that resemble it; and this is simply to class it as a tree. When he becomes more intelligent regarding it—when, for instance, he sees that it is an elm or an apple-tree-he simply perceives a larger number of characters of likeness and difference.

How our degrees of knowledge resolve themselves into successive classifications has been well illustrated by Herbert Spencer. He says: "The same object may, according as the distance or the degree of light permits, be identified as a particular negro; or, more generally, as a negro; or, more generally still, as a man; or, yet more generally, as some living creature; or most generally, as a solid body; in each of

which cases the implication is, that the present impression is like a certain order of past impressions.'

In early infancy, when the mind is first making the acquaintance of outward things, mental growth consists essentially in the production of new ideas by repetition of sensations, although such ideas never rise singly, but are always linked together in their origin. But, when a stock of ideas has been formed in this manner, the mental growth is mainly carried forward by new combinations among them. The simpler ideas once acquired, the development of intelligence consists largely in associating them in new relations and groups of relations. The perception of likeness and difference is the essential work that is going on all the time, but the comparisons and discriminations are constantly becoming more extensive, more minute, and more accurate. A number of elementary ideas

thus become, as it were, fused or consolidated into one complex idea; and, by a still further recognition of likeness and difference, this is classed with a new group, and this again with still larger clusters of associated ideas.

The conception of an orange, for example, is compounded of the elementary notions of colour, form, size, roughness, resistance, weight, odour, and taste. These elements are all bound up in one complex idea. The idea of an apple, a pear, a peach, or a plum, is in each case made up of a different group of component ideas, while the notion of a basket of different fruits is a cluster of these groups of still higher complexity, but still represented in thought as one complex idea, the elements of which are united by the relations of contrast and resemblance. Or, again, the child may begin with a large, vague idea, as a tree, for example, and then, as intelligence concerning it progresses, he decomposes it into its component

ideas, as trunk, branches, leaves, roots, and these into still minuter parts. There is a growing mental heterogeneity through the increasing perception of likeness and difference. Thus, as soon as ideas are formed, they begin to be used over and over, and this process is ever continued. An old idea in a new relation or grouping has a new meaning—becomes a new fact or a new truth. The perception of new resemblances and of new differences gives rise to new groupings and new classings of ideas, and thus the mind grows into a complex and highly differentiated organism of intelligence, in which the internal order of thought-relations answers to the external order of relations among things.

That which occurs at this earliest stage of mental growth is exactly what takes place in the whole course of unfolding intelligence. Simple as these operations may seem, and begun by the infant as soon as it is born, in their growing complexities, they constitute the whole fabric of the intellect. What we term the 'mental faculties' are not the ultimate elements of mind, but only different modes of the mental activity; and, as one law of growth evolves all the various organs and tissues of the bodily structure, so one law of growth evolves all the diversified faculties' of the mental structure. Under psychological analysis, the operations of reason,

Our reason consists in using an old fact in new circumstances, through the power of discerning the agreement; this is a vast saving of the labour of acquisition; a reduction of the number of original growths requisite for our education. When we have anything new to learn, as a new piece of music, or a new proposition in Euclid, we fall back upon our previouslyformed combinations, musical or geometrical, so far as they will apply, and merely tack certain of them together in correspondence with the new case, The method of acquiring by patch-work sets in early, and predominates increasingly.-Bain.