“Experience is the overcoming of perils. The word “experience” shares a common root (per) with “experiment,” “expert,” and “perilous.” To experience in the active sense requires that one venture forth into the unfamiliar and experiment with the elusive and the uncertain. To become an expert one must dare to confront the perils of the new. Why should one so dare? A human individual is driven. He is passionate, and passion is a token of mental force. The emotional repertoire of a clam is very restricted compared with that of a puppy; and the affective life of the chimpanzee seems almost as varied and intense as that of a human being. A human infant is distinguished from other mammalian young both by his helplessness and by his fearsome tantrums. The infant’s emotional range, from smile to tantrum, hints at his potential intellectual reach.”