Cialdini raamat
cient units (Ridley, 1997; Tiger ~ Fox, 1989).
It is a sense of future obligation that is critical to produce social advances of
the sort described by Tiger and Fox. A widely shared and strongly held feeling of
future obligation made an enormous difference in human social evolution because
it meant that one person could give something (for example, food, energy, care) to
another with confidence that the gift was not being lost. For the first time in evo-
lutionary history, one individual could give away any of a variety of resources with-
out actually giving them away. The result was the lowering of the natural
inhibitions against transactions that must be begun by one person's providing per-
sonal resources to another. Sophisticated and coordinated systems of aid, gift
giving, defense, and trade became possible, bringing immense benefits to the so-
cieties that possessed them. With such clearly adaptive consequences for the cul-
annaabi.ee 
