Emotion in animals specialised form of Occam's razor used in ethology, in which he stated: Charles Darwin initially planned to include a chapter on emotion in "The Descent of Man" but as his ideas progressed they expanded into a book, "The Expression of the Emotions in Man and Animals". Darwin proposed that emotions are adaptive and serve a communicative and motivational function, and he stated three principles that are useful in understanding emotional expression: First, "The Principle of Serviceable Habits" takes a Lamarckian stance by suggesting that emotional expressions that are useful will be passed on to the offspring. Second, "The Principle of
The Expression of the Emotions in Man and Animals West Yorkshire. Darwin corresponded intensively with James Crichton-Browne, the son of the phrenologist William A. F. Browne and now the medical director of the Wakefield asylum. At the time, Crichton-Browne was preparing his extremely influential "West Riding Lunatic Asylum Medical Reports", and Darwin remarked to him that "The Expression" "should be called by Darwin "and" Browne". Darwin also drew on his personal experience of the symptoms of bereavement and studied the text of Henry Maudsley's 1870 Gulstonian lectures on "Body and Mind". He considered other approaches to the study of emotions, including their depiction in the arts – discussed by