We learn to do new things, acquire new knowledge, and think new thoughts with toil. But practice brings facility. In the end we perform with ease that which was acquired with difficulty. We cannot, however, unlearn as we learnt, by an act of will. The facility lingers, and, as a consequence, our actions and thoughts, our mental attitudes, our whole outlook on life becomes more or less automatic and stereotyped. In other words, our acquirements come at last to resemble instincts, and are often so misnamed, as when a boy who has learned to dodge is said to avoid a blow instinctively. A being from another planet who for the first time saw a man walking or cycling could not distinguish the nature of these acquirements from such instinctive movements as the running or flying of an insect. The patriotism of a Spartan or a Japanese differs from that of a bee only in its mode of origin. In brief, the low animal is a creature of instincts, the man is a creature of habits, which are nothing other than imitation instincts. [Sidenote: Mankind’s Substitutes for Instinct] A principal function, then, of our faculty of making mental acquirements, of our conscious and unconscious memories, is to supply us with those automatic ways of thinking and acting which are our substitutes for instincts. Our conscious memories supply us with our stereotyped mental attitudes--desires, beliefs, aspirations, habitual way of thinking, and so forth. Our unconscious memories supply our stereotyped ways of acting--the automatic ways of acting we have just considered. It is a principal business of our lives to acquire them; but, though a great advantage is thus gained, one almost as great is lost. We act and think more quickly in familiar situations, but in proportion as we grow older we lose our splendid human capacity for learning. Beyond the verge of our imitation instincts spreads a domain, very wide in the infant, but narrowing as we pass towards old age, which is the real realm of the active intellect. Here, where thoughts and actions are not yet stereotyped, memory gathers fresh harvests, imagination plays, and reason ponders. Here man is a rational being in the strict sense of the word. [Sidenote: Mind and Memory]