The works of Antisthenes being lost, we do not know how he himself stated his own doctrine, nor what he said on behalf of it, declaring contradiction to be impossible. Plato sets aside the doctrine as absurd and silly; Aristotle--since he cites it as a paradox, apt for dialectical debate, where the opinion of a philosopher stood opposed to what was generally received--seems to imply that there were plausible arguments to be urged in its favour.[129] And that the doctrine actually continued to be held and advocated, in the generation not only after Antisthenes but after Aristotle--we may see by the case of Stilpon: who maintained (as Antisthenes had done) that none but identical propositions, wherein the predicate was a repetition of the subject, were admissible: from whence it followed (as Aristotle observed) that there could be no propositions either false or contradictory. Plutarch,[130] in reciting this doctrine of Stilpon (which had been vehemently impugned by the Epikurean Kolôtês), declares it to have been intended only in jest. There is no ground for believing that it was so intended: the analogy of Antisthenes goes to prove the contrary. [Footnote 129: Aristotle (Met. [Greek: D]. 1024) represents the doctrine of Antisthenes, That contradictory and false propositions are impossible--as a consequence deduced from the position laid down--That no propositions except identical propositions were admissible. If you grant this last proposition, the consequences will be undeniable. Possibly Antisthenes may have reasoned in this way:"There are many contradictory and false propositions now afloat; but this arises from the way in which predication is conducted. So long as the predicate is different from the subject, there is nothing _in the form of a proposition_ to distinguish falsehood from truth (to distinguish _Theætêtus sedet_, from _Theætêtus volat_--to take the instance in the Platonic Sophistês--p. 263). There ought to be no propositions except identical propositions: the form itself will then guarantee you against both falsehood and contradiction: you will be sure always to give [Greek: to\n oi)kei=on lo/gon tou= pra/gmatos]." There would be nothing inconsistent in such a precept: but Aristotle might call it silly [Greek: eu)êthô=s]), because, while shutting out falsehood and contradiction, it would also shut out the great body of useful truth, and would divest language of its usefulness as a means of communication.