By the ancients, Logic and Dialectic were used as synonymous terms; although [Greek: logizesthai], "to think over, to consider, to calculate," and [Greek: dialegesthai], "to converse," are two very different things. The name Dialectic was, as we are informed by Diogenes Laertius, first used by Plato; and in the _Phaedrus, Sophist, Republic_, bk. vii., and elsewhere, we find that by Dialectic he means the regular employment of the reason, and skill in the practice of it. Aristotle also uses the word in this sense; but, according to Laurentius Valla, he was the first to use Logic too in a similar way.[1] Dialectic, therefore, seems to be an older word than Logic. Cicero and Quintilian use the words in the same general signification.[2] [Footnote 1: He speaks of [Greek: dyscherelai logicai], that is, "difficult points," [Greek: protasis logicae aporia logicae]] [Footnote 2: Cic. _in Lucullo: Dialecticam inventam esse, veri et falsi quasi disceptatricem. Topica_, c. 2: _Stoici enim judicandi vias diligenter persecuti sunt, ea scientia, quam_ Dialecticen _appellant_. Quint., lib. ii., 12: _Itaque haec pars dialecticae, sive illam disputatricem dicere malimus_; and with him this latter word appears to be the Latin equivalent for Dialectic. (So far according to "Petri Rami dialectica, Audomari Talaei praelectionibus illustrata." 1569.)] This use of the words and synonymous terms lasted through the Middle Ages into modern times; in fact, until the present day. But more recently, and in particular by Kant, Dialectic has often been employed in a bad sense, as meaning "the art of sophistical controversy"; and hence Logic has been preferred, as of the two the more innocent designation. Nevertheless, both originally meant the same thing; and in the last few years they have again been recognised as synonymous.