In view of practice and social nature ,cognition is not only active but also comprehensive reflection . Cognition reflects not only the nature , relation , structure and function of object , but also the needs , ability , activity of subject and the relation between subject and object. Therefore , cognition is the comprehensive reflection of both subject and object. As long as we recognize the wide-ranging nature of the concept of matter , the inner relevance between subject and object , the disparity in c...