[The distinction between corporeal and incorporeal substance is one that Augustin often insists upon. See Confessions VII. i-iii. The doctrine that all substance is extended body, and that there is no such entity as spiritual unextended substance, is combatted by Plato in the Theatetus. For a history of the contest and an able defence of the substantiality of spirit, see Cudworth’s Intellectual System, III. 384 sq. Harrison’s Ed.—W.G.T.S.]