1. Definition. Principle, ἀρχή in Greek, means literally beginning, origin, and designates in general that from which something proceeds in some way. Hence if we are speaking of really existent things, the principle is the cause of something that comes to be, or of an event, though it may also be the inward centre of a being, by which it lives and acts (“vital principle”). So too principle is used to designate the elements of which a whole is composed, such as the ontological constituents of con…