Note 159 — Chapter XV · WHEN DID LAMARCK CHANGE HIS VIEWS REGARDING THE MUTABILITY OF SPECIES?

While Rousseau was living at Montmorency “his thought wandered confusedly round the notion of a treatise to be called ‘Sensitive Morality or the Materialism of the Age,’ the object of which was to examine the influence of external agencies, such as light, darkness, sound, seasons, food, noise, silence, motion, rest, on our corporeal machine, and thus, indirectly, upon the soul also.”—Rousseau, by John Morley (p. 164).