This book represents the very first, so far unpublished, translation of Piotr Galperin’s (1902-1988) dissertation, defended in 1938 during his employment in the All-Ukrainian Psycho-Neurological Academy (AUPA) in Kharkiv, Ukraine. In his candidate dissertation Galperin examined the differences in tool use between humans and animals and argued that there was a fundamental difference between tools developed and used by humans and the auxiliary means used by animals. Galperin showed that human use of tools totally differs from the way tools are utilised by animals as ‘an extension’ of...