Janus: A summing up

Written towards the end of his life this book serves as a summation of Koestler's earlier scientific writings, including "The Act of Creation," "The Case of the Midwife Toad" and "The Ghost in the Machine." He defines an hypothesis of "schizophysiology, which he sees as singularly human. It seeks to explain "the chronic, quasi-schizophrenic split between reason and emotion" and uses an evolutionary argument.