Reasoning processes allow the human cognitive system to go beyond the infor
mation readily available in the environment. This review focuses on the pro
cesses of human thinking, including deductive reasoning, induction, mental
simulation, and analogy. We survey recent trends across several areas, incl
uding categorization, mental models, cognitive development, and decision ma
king. Our chief organizing principle is the contrast between traditional ap
proaches that focus on abstract logical reasoning and a number of current a
pproaches that posit domain-specific, knowledge-intensive cognition. We sug
gest that some instances of domain-specific cognition result from domain-ge
neral processes operating on domain-specific representations. Another theme
is the link between reasoning and learning. We suggest that learning typic
ally occurs as a byproduct of reasoning, rather than as an end in itself.