ABSTRACT
During the mid-twentieth century, Darwin's suggestion that group-selection was the source of our sociability was, of course, suppressed because this form of selection was then believed to be impossible. At that time, evolutionists made selection at only one level into a compulsory orthodoxy. Rationality demanded (it seemed) that competition should take place only between a single set of rivals: evolutionary atoms that profited individually from the process. These units, which at first had seemed to be whole organisms, were finally deemed to be the genes and were treated as independent agents in a way that seemed to credit them with having purposes of their own. The imagery of "selfishness", which expressed the supposed isolation and eager activity of these rivals, was seen as crucial for the process.
