The true art of rhetoric (continues Sokrates) embraces a larger range than these teachers imagine. It deals with mind, as the medical researches of Hippokrates deal with body--as a generic total with all its species and varieties, and as essentially relative to the totality of external circumstances. First, Hippokrates investigates how far the body is, in every particular man, simple, homogeneous, uniform: and how far it is complex, heterogeneous, multiform, in the diversity of individuals. If it be one and the same, or in so far as it is one and the same, he examines what are its properties in relation to each particular substance acting upon it or acted upon by it. In so far as it is multiform and various, he examines and compares each of the different varieties, in the same manner, to ascertain its properties in relation to every substance.[74] It is in this way that Hippokrates discovers the nature or essence of the human body, distinguishing its varieties, and bringing the medical art to bear upon each, according to its different properties. This is the only scientific or artistic way of proceeding. [Footnote 74: Plato, Phædrus, p. 270 D. [Greek: A)=r' ou)ch ô(=de dei= dianoei=sthai peri\ o(touou=n phu/seôs? Prô=ton me\n, a(plou=n ê)\ polueide/s e)stin, ou(= peri\ boulêso/metha ei)=nai au)toi\ technikoi\ kai\ a)/llon dunatoi\ poiei=n? e)/peita de/, e)a\n me\n a(plou=n ê)=|, skopei=n tê\n du/namin au)tou=, ti/na pro\s ti/ pe/phuken ei)s to\ dra=|n e)/chon ê)\ ti/na ei)s to\ pathei=n u(po\ tou=? e)a\n de\ plei/ô ei)/dê e)/chê|, tau=ta a)rithmêsa/menos, o(/per e)ph' e(no/s, tou=t' i)dei=n e)ph' e(ka/stou, tô=| ti/ poiei=n au)to\ pe/phuken ê)\ tô=| ti/ pathei=n u(po\ tou=?]] [Side-note: Art of Rhetoric ought to include a systematic classification of minds with all their varieties, and of discourses with all their varieties. The Rhetor must know how to apply the one to the other, suitably to each particular case.]