The central concern of this book, first published in 1966 and now reprinted, is to show the hard core of philosophic argument which runs through all Sartre's works and which marks him, more than any other single feature of his writings, as one of the great figures of our time. Mr Manser's critical exposition of Sartre's thought seeks to avoid terms which bring with them pre-conceived attitudes and to help the reader to judge for himself the strengths and weaknesses of the ideas presented.