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 Constitution of Man Supremacy of the Moral Sentiments and Intellect," Combe goes on to argue that the moral sentiments are superior to those that men share with animals, and that the faculties "are right only when directed by "enlightened" intellect and moral sentiment..."they must be illuminated by knowledge of science and of moral and religious duty,"" or else the result is evil. A delicate balance of the expression of the faculties is required for man's happiness. In Section five, "The Faculties of Man Compared with External Objects," Combe identifies specific faculties and their effects on the eternal world. For example, with Philoprogenitiveness, the