Series III. Human Problem Solving -- 1957-1971 (1992) comprises two and one-quarter boxes (2.25 cu. ft.). It contains draft copies of the book, dated 1969-1970, and early drafts and notes dated 1959-1961, 1967 -- substantiating Simon's claims that the project's conception began as early as 1958. The drafts are divided into chapters and several copies of each chapter are represented. Many draft items were distributed to others in the artificial intelligence and psychology communities and later returned to Newell and Simon with comments and questions. Study of the drafts reveals the authors' processes in going from initial concept to publishable manuscript.