[Review of the research on "theory of mind"]

The concept "theory of mind", first proposed by Premack and Woodruff (1978), has drastically changed our view of the mind. In the first half of this paper, the concept's history and recent developments were reviewed. Included were studies of non-human primates, normal children, and autistic children, in addition to some philosophical discussions. The "false belief" paradigm has been successful in understanding children older than 4 years and in characterizing children with high-functioning autism. But with the paradigm alone, it is difficult to explain the "mind" of most non-human primates, younger children, and a large part of autistic children. In the second half, a theoretical discussion was made to understand early developments of mind. The theory theory and competing theories of modularity, simulation, and intersubjectivity were compared concerning the observability of mind (of self and others), the basic mechanisms for understanding the mind, the indispensability of theorizing the mind, and the need for metarepresentation in pretend plays.