The ascendancy of Sokrates over his contemporaries was powerfully exercised in more than one way. He brought into vogue new subjects both of indefinite amplitude, and familiar as well as interesting to every one. On these subjects, moreover, he introduced, or at least popularised, a new method of communication, whereby the relation of teacher and learner, implying a direct transfer of ready-made knowledge from the one to the other, was put aside. He substituted an interrogatory process, at once destructive and suggestive, in which the teacher began by unteaching and the learner by unlearning what was supposed to be already known, for the purpose of provoking in the learner's mind a self-operative energy of thought, and an internal generation of new notions. Lastly, Sokrates worked forcibly upon the minds of several friends, who were in the habit of attending him when he talked in the market-place or the palæstra. Some tried to copy his wonderful knack of colloquial cross-examination: how far they did so with success or reputation we do not know: but Xenophon says that several of them would only discourse with those who paid them a fee, and that they thus sold for considerable sums what were only small fragments obtained gratuitously from the rich table of their master.[2] There were moreover several who copied the general style of his colloquies by composing written dialogues. And thus it happened that the great master,--he who passed his life in the oral application of his Elenchus, without writing anything,--though he left no worthy representative in his own special career, became the father of numerous written dialogues and of a rich philosophical literature.[3] [Footnote 2: Xenophon, Memor. i. 2, 60. [Greek: ô(=n tine\s mikra\ me/rê par' e)kei/nou proi=ka labo/ntes pollou= toi=s a)/llois e)pô/loun, kai\ ou)k ê)=san ô(/sper e)kei=nos dêmotikoi/; toi=s ga\r mê\ e)/chousi chrê/mata dido/nai ou)k ê)/thelon diale/gesthai.]]