The acquisition of definiteness and of coherency (or constancy) of meanings is derived primarily from practical activities. By rolling an object, the child makes its roundness appreciable; by bouncing it, he singles out its elasticity; by throwing it, he makes weight its conspicuous distinctive factor. Not through the senses, but by means of the reaction, the responsive adjustment, is the impression made distinctive, and given a character marked off from other qualities that call out unlike reactions. Children, for example, are usually quite slow in apprehending differences of color. Differences from the standpoint of the adult so glaring that it is impossible not to note them are recognized and recalled with great difficulty. Doubtless they do not all _feel_ alike, but there is no intellectual recognition of what makes the difference. The redness or greenness or blueness of the object does not tend to call out a reaction that is sufficiently peculiar to give prominence or distinction to the color trait. Gradually, however, certain characteristic habitual responses associate themselves with certain things; the white becomes the sign, say, of milk and sugar, to which the child reacts favorably; blue becomes the sign of a dress that the child likes to wear, and so on: and the distinctive reactions tend to single out color qualities from other things in which they had been submerged. [Sidenote: We identify by use or function] Take another example. We have little difficulty in distinguishing from one another rakes, hoes, plows and harrows, shovels and spades. Each has its own associated characteristic use and function. We may have, however, great difficulty in recalling the difference between serrate and dentate, ovoid and obovoid, in the shapes and edges of leaves, or between acids in _ic_ and in _ous_. There is some difference; but just what? Or, we know what the difference is; but which is which? Variations in form, size, color, and arrangement of parts have much less to do, and the uses, purposes, and functions of things and of their parts much more to do, with distinctness of character and meaning than we should be likely to think. What misleads us is the fact that the qualities of form, size, color, and so on, are _now_ so distinct that we fail to see that the problem is precisely to account for the way in which they originally obtained their definiteness and conspicuousness. So far as we sit passive before objects, they are not distinguished out of a vague blur which swallows them all. Differences in the pitch and intensity of sounds leave behind a different feeling, but until we assume different attitudes toward them, or _do_ something special in reference to them, their vague difference cannot be _intellectually_ gripped and retained. [Sidenote: Children's drawings illustrate domination by value]