distinct or vague, in our mind, disconnected with bcd, then that constituent a may be analyzed out from the total impression. Analysis of a thing means separate attention to each of its parts. In Chapter XIII we saw that one condition of attending to a thing was the formation from within of a separate image of that thing, which should, as it were, go out to meet the impression received. Attention being the condition of analysis, and separate imagination being the condition of attention, it follows also that separate imagination is the condition of analysis. Only such elements as we are acquainted with, and can imagine separately, can be discriminated within a total sense-impression. The image seems to welcome its own mate from out of the compound, and to separate it from the other constituents; and thus the compound becomes broken for our consciousness into parts.

All the facts cited in Chapter XIII to prove that attention involves inward reproduction prove that discrimination involves it as well. In looking for any object in a room, for a book in a library, for example, we detect it the more readily if, in addition to merely knowing its name, etc., we carry in our mind a distinct image of its appearance. The assafœdita in Worcestershire sauce' is not obvious to anyone who has not tasted assafoetida per se. In a 'cold' color an artist would never be able to analyze out the pervasive presence of blue, unless he had previously made acquaintance with the color blue by itself. All the colors we actually experience are mixtures. Even the purest primaries always come to us with some white. Absolutely pure red or green or violet is never experienced, and so can never be discerned in the so-called primaries with which we have to deal: the latter consequently pass for pure.The reader will remember how an overtone can only be attended to in the midst of its consorts in the voice of a musical instrument, by sounding it previously alone. The imagination, being then full of it, hears the like of it in the compound tone.

Non-isolable elements may be discriminated, provided

their concomitants change. Very few elements of reality are experienced by us in absolute isolation. The most that usually happens to a constituent a of a compound phenomenon abcd is that its strength relatively to bcd varies from a maximum to a minimum; or that it appears linked with other qualities, in other compounds, as aefg or ahik. Either of these vicissitudes in the mode of our experiencing a may, under favorable circumstances, lead us to feel the difference between it and its concomitants, and to single it out-not absolutely, it is true, but approximately—and so to analyze the compound of which it is a part. The act of singling out is then called abstraction, and the element disengaged is an abstract.

Fluctuation in a quality's intensity is a less efficient aid to our abstracting of it than variety in the combinations in which it appears. What is associated now with one thing and now with another tends to become dissociated from either, and to grow into an object of abstract contemplation by the mind. One might call this the law of dissociation by varying concomitants. The practical result of this law is that a mind which has once dissociated and abstracted a character by its means can analyze it out of a total whenever it meets with it again.

Dr. Martineau gives a good example of the law: "When a red ivory ball, seen for the first time, has been withdrawn, it will leave a mental representation of itself, in which all that it simultaneously gave us will indistinguishably coexist. Let a white ball succeed to it; now, and not efore, will an attribute detach itself, and the color, by force of contrast, be shaken out into the foreground. Let the white ball be replaced by an egg, and this new difference will bring the form into notice from its previous slumber, and thus that which began by being simply an object cut out from the surrounding scene becomes for us first a red object, then a red round object, and so on."

Why the repetition of the character in combination with different wholes will cause it thus to break up its adhesion with any one of them, and roll out, as it were, alone upon

the table of consciousness, is a little of a mystery, but one which need not be considered here.

Practice improves Discrimination.-Any personal or practical interest in the results to be obtained by distinguishing, makes one's wits amazingly sharp to detect differences. And long training and practice in distinguishing has the same effect as personal interest. Both of these agencies give to small amounts of objective difference the same effectiveness upon the mind that, under other circumstances, only large ones would have.

That 'practice makes perfect' is notorious in the field of motor accomplishments. But motor accomplishments depend in part on sensory discrimination. Billiard-playing, rifle-shooting, tight-rope-dancing demand the most delicate appreciation of minute disparities of sensation, as well as the power to make accurately graduated muscular response thereto. In the purely sensorial field we have the well-known virtuosity displayed by the professional buyers and testers of various kinds of goods. One man will distinguish by taste between the upper and the lower half of a bottle of old Madeira. Another will recognize, by feeling the flour in a barrel, whether the wheat was grown in Iowa or Tennessee. The blind deaf-mute, Laura Bridgman, so improved her touch as to recognize, after a year's interval, the hand of a person who once had shaken hers; and her sister in misfortune, Julia Brace, is said to have been employed in the Hartford Asylum to sort the linen of its multitudinous inmates, after it came from the wash, by her wonderfully educated sense of smell.

The fact is so familiar that few, if any, psychologists have even recognized it as needing explanation. They have seemed to think that practice must, in the pature of things, improve the delicacy of discernment, and have let the matter rest. At most they have said, "Attention accounts for it; we attend more to habitual things, and what we attend to we perceive more minutely." This answer, though true, is too general; but we can say nothing more about the matter here.

CHAPTER XVI.

ASSOCIATION.

The Order of our Ideas.-After discrimination, association! It is obvious that all advance in knowledge must consist of both operations; for in the course of our education, objects at first appearing as wholes are analyzed into parts, and objects appearing separately are brought together and appear as new compound wholes to the mind. (Analysis and synthesis are thus the incessantly alternating mental activities, a stroke of the one preparing the way for a stroke of the other, much as, in walking, a man's two legs are alternately brought into use, both being indispensable for any orderly advance.

The manner in which trains of imagery and consideration follow each other through our thinking, the restless flight of one idea before the next, the transitions our minds make between things wide as the poles asunder, transitions which at first sight startle us by their abruptness, but which, when scrutinized closely, often reveal intermediating links of perfect naturalness and propriety-all this magical, imponderable streaming has from time immemorial excited the admiration of all whose attention happened to be caught by its omnipresent mystery. And it has furthermore challenged the race of philosophers to banish something of the mystery by formulating the process in simpler terms.The problem which the philosophers have set themselves is that of ascertaining, between the thoughts which thus appear to sprout one out of the other, principles of connection whereby their peculiar succession or coexistence may be explained.)

But immediately an ambiguity arises: which sort of

connection is meant ? connection thought-of, or connection between thoughts? These are two entirely different things, and only in the case of one of them is there any hope of finding principles.' The jungle of connections thought of can never be formulated simply. Every conceivable connection may be thought of-of coexistence, succession, resemblance, contrast, contradiction, cause and effect, means and end, genus and species, part and whole, substance and property, early and late, large and small, landlord and tenant, master and servant,-Heaven knows what, for the list is literally inexhaustible. The only simplification which could possibly be aimed at would be the reduction of the relations to a small number of types, like those which some authors call the 'categories' of the understanding. According as we followed one category or another we should sweep, from any object with our thought, in this way or in that, to others. Were this the sort of connection sought between one moment of our thinking and another, our chapter might end here. For the only summary description of these categories is that they are all thinkable relations, and that the mind proceeds from one object to another by some intelligible path.

Is it determined by any laws? But as a matter of fact, What determines the particular path? Why do we at a given time and place proceed to think of b if we have just thought of a, and at another time and place why do we think, not of b, but of c? Why do we spend years straining after a certain scientific or practical problem, but all in vain—our thought unable to evoke the solution we desire? And why, some day, walking in the street with our attention miles away from that quest, does the answer saunter into our minds as carelessly as if it had never been called for-suggested, possibly, by the flowers on the bonnet of the lady in front of us, or possibly by nothing that we can discover?

The truth must be admitted that thought works under strange conditions. Pure 'reason' is only one out of a

We are

to rub the prisiple of nectado etwas thought.