Traditional approaches to causal attribution propose that information
about covariation of factors is used to identify causes of events. In
contrast, we present a series of studies showing that people seek out
and prefer information about causal mechanisms rather than information
about covariation. Experiments 1, 2 and 3 asked subjects to indicate
the kind of information they would need for causal attribution. The su
bjects tended to seek out information that would provide evidence for
or against hypotheses about underlying mechanisms. When asked to provi
de causes, the subjects' descriptions were also based on causal mechan
isms. In Experiment 4, subjects received pieces of conflicting evidenc
e matching in covariation values but differing in whether the evidence
included some statement of a mechanism. The influence of evidence was
significantly stronger when it included mechanism information. We con
clude that people do not treat the task of causal attribution as one o
f identifying a novel causal relationship between arbitrary factors by
relying solely on covariation information. Rather, people attempt to
seek out causal mechanisms in developing a causal explanation for a sp
ecific event.