After Helvetius, my father made me study what he deemed the really master-production in the philosophy of mind, Hartley's _Observations on Man_.

This book, though it did not, like the _Traite de Legislation_, give a new colour to my existence, made a very similar impression on me in regard to its immediate subject.

Hartley's explanation, incomplete as in many points it is, of the more complex mental phenomena by the law of association, commended itself to me at once as a real analysis, and made me feel by contrast the insufficiency of the merely verbal generalizations of Condillac, and even of the instructive gropings and feelings about for psychological explanations, of Locke.

It was at this very time that my father commenced writing his _Analysis_ of the Mind, which carried Hartley's mode of explaining the mental phenomena to so much greater length and depth.

He could only command the concentration of thought necessary for this work, during the complete leisure of his holiday for a month or six weeks annually: and he commenced it in the summer of 1822, in the first holiday he passed at Dorking; in which neighbourhood, from that time to the end of his life, with the exception of two years, he lived, as far as his official duties permitted, for six months of every year.