  In De Anima, Aristotle makes extensive use of technical terminology introduced and explained elsewhere in his writings. He claims, for example, using vocabulary derived from his physical and metaphysical theories, that the soul is a “first actuality of a natural organic body” (De Anima ii 1, 412b5–6), that it is a “substance as form of a natural body which has life in potentiality” (De Anima ii 1, 412a20–1) and, similarly, that it “is a first actuality of a natural body which has life in potentiality” (De Anima ii 1, 412a27–8), all claims which apply to plants, animals and humans alike.