We begin with what seems a paradox. The world of experience of any man is composed of a tremendous array of discriminably different objects, events, people, impressions. There are estimated to be more that 7 million discriminable colors alone ... [and even subtle differences] we are capable of seeing, for human beings have an exquisite capacity for making distinctions. But were we to utilize fully our capacity for registering the differences in things and to respond to each event encountered as unique, we would soon be overwhelmed by the complexity of our environment... [It] would make us slaves to the particular... [The resolution to this paradox] is achieved by man's capacity to categorize. To categorize is to render discriminably different things equivalent, to group the objects and events and people around us into classes and to respond to them in terms of their class membership.
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