Abstract
This chapter introduces psychologism as the thesis that social facts can explained in terms of more basic facts about individuals, their psychological states, their actions, their relations, and their environments. It argues psychologism should be our default stance toward social reality. It reviews psychologistic approaches to shared intention and how shared intentions can help explain conventions, status functions, and organizations. It provides a deflationary account of corporate attitudes. It argues that neither physical nor social externalism about thought content are incompatible with psychologism. It argues that social construction views of the self that conflict with psychologism are implausible. Finally, it points out that it is no objection to psychologism that social facts can change without changes in psychological facts because this is compatible with psychologism as explained here.