In 1904 he published an autobiography entitled "Biographia philosophica", in which he sketched the progress of his intellectual development. From this work and from his Gifford Lectures (1894–96) we learn objectively what had previously been inferred from his critical work. After a childhood spent in an austerity which stigmatised as unholy even the novels of Sir Walter Scott, he began his college career at the age of fourteen at a time when Christopher North and Dr Ritchie were lecturing on Moral Philosophy and Logic. His first philosophical advance was stimulated by Thomas Brown's "Cause and Effect", which introduced him to the problems which were to occupy his thought. From this point he embraced the scepticism of David Hume.