Full Idea
Theoretical reason is typically a matter of accepting a conclusion or hypothesis on the basis of argument or evidence, and is thus a special case of practical reason.
Gist of Idea
Theory involves accepting conclusions, and so is a special case of practical reason
Source
John Searle (Rationality in Action [2001], Ch.3.VII)
Book Reference
Searle,John R.: 'Rationality in Action' [MIT 2001], p.90