TALK IS CHEAP

IN sender-reciever situations where the transfer of information is in the interest of both parties, signals spontaneously acquire meaning and act to promote the common interest. But what about types of interaction that do not have this ideal structure? Some people may want to withhold information, or to transmit misinformation. Concealment and deception also are used by organisms other than humans. Every potential employee wants to convince employers that she is intelligent and hardworking. Every antelope would like to convince the wolf that she is too fast to catch. Nobel laureate in economics A. Michael Spence and later evolutionary biologist Amotz Zahavi suggested that in such situations, we might find considerable resources expended on signals that are too costly to fake. A degree in classics from Harvard may represent acquisition of knowledge irrelevant to an occupation but still serve as a reliable signal of intelligence and enterprise. A conspicuous vertical leap by an antelope may serve as a reliable signal of speed and evasive capability. Zahavi's “Handicap Principle” makes cost the key element in the analyis of the evolution of signaling. Given these developments, it is easy to be skeptical about the efficacy of costless signals in situations that lack the ideal structure of David Lewis's sender-receiver games. Talk is cheap.