THE NECESSITY FOR GROWING CONCEPTS.--The development of our concepts constitutes a large part of our education. For it is evident that, since thinking rests so fundamentally on concepts, progress in our mental life must depend on a constant growth in the number and character of our concepts. Not only must we keep on adding new concepts, but the old must not remain static. When our concepts stop growing, our minds have ceased to grow--we no longer learn. This arrest of development is often seen in persons who have settled into a life of narrow routine, where the demands are few and of a simple nature. Unless they rise above their routine, they early become "old fogies." Their concepts petrify from lack of use and the constant reconstruction which growth necessitates. On the other hand, the person who has upon him the constant demand to meet new situations or do better in old ones will keep on enriching his old concepts and forming new ones, or else, unable to do this, he will fail in his position. And the person who keeps on steadily enriching his concepts has discovered the secret of perpetual youth so far as his mental life is concerned. For him there is no old age; his thought will be always fresh, his experience always accumulating, and his knowledge growing more valuable and usable. 5. JUDGMENT But in the building up of percepts and concepts, as well as in making use of them after they are formed, another process of thinking enters; namely, the process of _judging_. NATURE OF JUDGMENT.--Judging enters more or less into all our thinking, from the simplest to the most complex. The babe lies staring at his bottle, and finally it dawns on his sluggish mind that this is the object from which he gets his dinner. He has performed a judgment. That is, he has alternately directed his attention to the object before him and to his image of former nursing, discovered the relation existing between the two, and affirmed to himself, "This is what gives me my dinner." "Bottle" and "what-gives-me-my-dinner" are essentially identical to the child. _Judgment is, then, the affirmation of the essential identity of meaning of two objects of thought._ Even if the proposition in which we state our judgment has in it a negative, the definition will still hold, for the mental process is the same in either case. It is as much a judgment if we say, "The day is not-cold," as if we say, "The day is cold."