Now the true rhetor ought to deal with the human mind in like manner. His task is to work persuasion in the minds of certain men by means of discourse. He has therefore, first, to ascertain how far all mind is one and the same, and what are the affections belonging to it universally in relation to other things: next, to distinguish the different varieties of minds, together with the properties, susceptibilities, and active aptitudes, of each: carrying the subdivision down until he comes to a variety no longer admitting division.[75] He must then proceed to distinguish the different varieties of discourse, noting the effects which each is calculated to produce or to hinder, and the different ways in which it is likely to impress different minds.[76] Such and such men are persuadable by such and such discourses--or the contrary. Having framed these two general classifications, the rhetor must on each particular occasion acquire a rapid tact in discerning to which class of minds the persons whom he is about to address belong: and therefore what class of discourses will be likely to operate on them persuasively.[77] He must farther know those subordinate artifices of speech on which the professors insist; and he must also be aware of the proper season and limit within which each can be safely employed.[78] [Footnote 75: Plato, Phædrus, p. 277 B. [Greek: o(risa/meno/s te pa/lin kat' ei)/dê me/chri tou= a)tmê/tou te/mnein e)pistêthê=|.]] [Footnote 76: Plato, Phædrus, p. 271 A. [Greek: _Prô=ton_, pa/sê| a)kribei/a| gra/psei te kai\ poiê/sei psuchê\n i)dei=n, po/teron e(\n kai\ o(/moion pe/phuken ê)\ kata\ sô/matos morphê\n polueide/s; tou=to ga/r phamen _phu/sin_ ei)=nai deiknu/nai. _Deu/teron_ de/ ge, o(/tô| ti/ poiei=n ê)\ pathei=n u(po\ tou= pe/phuken. _Tri/ton_ de\ dê\ diataxa/menos ta\ lo/gôn te kai\ psuchê=s ge/nê kai\ ta\ tou/tôn pathê/mata, di/eisi ta\s ai)ti/as, prosarmo/ttôn e(/kaston e(ka/stô|, kai\ dida/skôn oi(/a ou)=sa u(ph' oi(/ôn lo/gôn di' ê(\n ai)ti/an e)x a)na/gkês ê( me\n pei/thetai, ê( de\ a)peithei=.]] [Footnote 77: Plato, Phædrus, p. 271 D. [Greek: dei= mê\ tau=ta i(kanô=s noê/santa, meta\ tau=ta theô/menon au)ta\ e)n tai=s pra/xesin o)/nta te kai\ pratto/mena, _o)xe/ôs_ tê=| ai)sthê/sei du/nasthai e)pakolouthei=n], &c.] [Footnote 78: Plato, Phædrus, p. 272 A. [Greek: tau=ta de\ ê)/dê pa/nt' e)/chonti, _proslabo/nti kairou\s tou= po/te lekte/on kai\ e)pischete/on_, brachulogi/as te au)= kai\ e)leeinologi/as kai\ deinô/seôs, e(ka/stôn te o(/s' a)\n ei)/dê ma/thê| lo/gôn, tou/tôn _tê\n eu)kairi/an te kai\ a)kairi/an diagno/nti_, kalô=s te kai\ tele/ôs e)sti\n ê( te/chnê a)peirgasme/nê, _pro/teron d' ou)/_.]] [Side-note: The Rhetorical Artist must farther become possessed of real truth, as well as that which his auditors believe to be truth. He is not sufficiently rewarded for this labour.]