'I was re[a]ding lately, Stewart's "life of Robertson", Smith's "wealth of nations", and Kames' "Essays on the principles of morality". The first is a sensible sort of book - unworthy, however, of Stewart. Dr Smith is a man of much research, & appears to understand completely all the bearings of his complicated subject. I have read his first and second volumes with much pleasure. He always writes like a philosopher. With regard to Lord Kames - his works are generally all an awkward compound of ingenuity and absurdity and in this volume the latter quality it appears to me, considerably preponderates. It is Metaphysical; upon Belief, identity, Necessity &c &c and I devoutly wish that no friend of mine may ever come to study it - unless he wish to learn - To weave fine cobwebs fit for scull That's empty when the moon is full. - and in that case he cannot study under a more proper master.'