Deontology (τὸ δέον, what is due or binding; and λόγος, discourse). We take the following citations on the use of this word from Fleming, Vocabulary of Philosophy (Phila. 1860), s.v.: "Deontology, or that which is proper, has been chosen as a fitter term than any other which could be found to represent, in the field of morals, the principle of utilitarianism, or that which is useful" (Bentham, Deontology, or the Science of Morals). On the other hand, Whewell (Preface to Mackintosh's Prelim. Dissert. p. 20) says that "the term deontology expresses moral science, and expresses it well, precisely because it signifies the science of duty, and contains no reference to utility." Deontology involves the being bound or being under obligation, the very idea which utility does not give. "The ancient Pythagoreans defined virtue to be "῞Εξις τοῦ δέοντος (that is, the habit of duty, or of doing what is binding), the oldest definition of virtue of which we have any account, and one of the most unexceptionable which is yet to be found in any system of philosophy" (Stewart, Active and Moral Powers, 2:446). Sir W. Hamilton observes that ethics are "well denominated deontology" (Reid's Works , p. 540, note).