Contraries
Contraries
(a) Logic(i) TermsAccording to Aristotle, Categ. 1lb-18, contrariety is one of the four kinds of opposition between conceptscontradictory, privative, contrary, relative. Those terms are contrary “which, in the same genus, are separated by the greatest possible difference” ib. 6a-17. Thus pairs of contraries belong to the same genus, or contrary sub-genera, or are themselves sub-genera, ib. 14a-18.
Strictly speaking, there are no contraries in the category of substance, since substances are the subject of contraries, nor in the category of quantity, since these are relative. Two contrary states cannot obtain in one and the same individual at the same time and in the same respect; cf. contradiction. Some contraries, e.g. good-bad, black-white, have intermediaries; while others do not, e.g. odd-even. (ii) PropositionsTwo universal propositions, having opposite quality (i.e. one affirmative and one negative) are contrary; De Interpretattone, 17b-4, See Logic, formal 4, 8.
(b) PhysicsIn Greek philosophy, the ultimate principles of nature and change were contrariese.g. love-strife; motion-rest; potentiality-actuality. All motion is between contraries. See Heraclitus, Empedodes, Aristotle. — L.M.H.