nih.gov | Why are people interested in money? Specifically, what could be the
biological basis for the extraordinary incentive and reinforcing power
of money, which seems to be unique to the human species? We identify two
ways in which a commodity which is of no biological significance in
itself can become a strong motivator. The first is if it is used as a
tool, and by a metaphorical extension this is often applied to money: it
is used instrumentally, in order to obtain biologically relevant
incentives. Second, substances can be strong motivators because they
imitate the action of natural incentives but do not produce the fitness
gains for which those incentives are instinctively sought. The classic
examples of this process are psychoactive drugs, but we argue that the
drug concept can also be extended metaphorically to provide an account
of money motivation. From a review of theoretical and empirical
literature about money, we conclude that (i) there are a number of
phenomena that cannot be accounted for by a pure Tool Theory of money
motivation; (ii) supplementing Tool Theory with a Drug Theory enables
the anomalous phenomena to be explained; and (iii) the human instincts
that, according to a Drug Theory, money parasitizes include trading
(derived from reciprocal altruism) and object play.
