This debate contrasts interpretive and cognitive approaches to explaining teachers' thoughts and actions, exploring epistemological and ontological assumptions that broadly underlie research on teaching. Fundamental to the discussion is whether cognition should be construed as individual mental processing of privately held information structures or as a social event in which thinking is situated, shared, intersubjective, and practical. Also addressed is whether an effective explanation of teaching can rest mainly on an account of a teacher's cognition or whether it must attend equally to an examination of the place in which the teaching occurs and, if the latter, how place exerts its influence.