Aristotle "says that 'on the subjec

Aristotle "says that 'on the subject of reasoning' he 'had nothing else on an earlier date to speak of'".[17] However, Plato reports that syntax was devised before him, by Prodicus of Ceos, who was concerned by the correct use of words. Logic seems to have emerged from dialectics; the earlier philosophers made frequent use of concepts like reductio ad absurdum in their discussions, but never truly understood the logical implications. Even Plato had difficulties with logic; although he had a reasonable conception of a deductive system, he could never actually construct one, thus he relied instead on his dialectic.[18]