Functionalism as a philosophical theory of the cognitive sciences.

Functionalism is a philosophical theory (or family of theories) concerning the nature of mental states. According to functionalism psychological/cognitive states are essentially functional states of whole systems. Functionalism characterizes psychological states essentially according to what they do, by their relations to stimulus inputs and behavioral outputs as well as their relations to other psychological and nonpsychological internal states of a system. The central constructive relation for functionalism is the so-called realization relation. Realization is a proposal for how psychological states can be real, physical, and causally efficacious while at the same time preserving the autonomy of cognitive explanations and avoiding reduction or elimination. WIREs Cogn Sci 2012, 3:337-348. doi: 10.1002/wcs.1170 For further resources related to this article, please visit the WIREs website.