The arguments advanced against this doctrine from the phenomena of dreams, distempers, or insanity, admit (continues Sokrates) of a satisfactory answer. A man who is dreaming, sick, or mad, believes in realities different from, and inconsistent with, those which he would believe in when healthy. But this is because he is, under those peculiar circumstances, a different Subject, unlike what he was before. One of the two factors of the result being thus changed, the result itself is changed.[40] The cardinal principle of Protagoras--the essential correlation, and indefeasible fusion, of Subject and Object, exhibits itself in a perpetual series of definite manifestations. To say that I (the Subject) perceive,--is to say that I perceive some Object: to perceive and perceive nothing, is a contradiction. Again, if an Object be sweet, it must be sweet to some percipient Subject: sweet, but sweet to no one, is impossible.[41] Necessity binds the essence of the percipient to that of something perceived: so that every name which you bestow upon either of them implies some reference to the other; and no name can be truly predicated of either, which implies existence (either perpetual or temporary) apart from the other.[42] [Footnote 40: Plato, Theætêt. p. 159.] [Footnote 41: Plato, Theætêt. p. 160 A.] [Footnote 42: Plato, Theætêt. p. 160 B. [Greek: e)/peiper ê(mô=n ê( a)na/gkê tê\n ou)si/an sundei= me/n, sundei= de ou)deni\ tô=n a)/llôn, ou)d' au)= ê(mi=n au)toi=s; a)llê/lois dê\ lei/petai sundede/sthai] (_i. e._ [Greek: to\n ai)sthano/menon] and [Greek: to\ poiou=n ai)stha/nesthai]). [Greek: Ô/ste ei)/te _tis ei)=nai ti/ o)noma/zei, tini\ ei)=nai, ê)\ tino/s, ê)\ pro/s ti, r(ête/on au)tô=|, ei)/te gi/gnesthai; au)to\ de\ e)ph' au(tou= ti ê)\ o)\n ê)\ gigno/menon ou)/te au)tô=| lekte/on, ou)/t' a)/llou le/gontos a)podekte/on_.] Compare Aristot. Metaphys. [Greek: G]. 6, p. 1011, a. 23.] [Side-note: Exposition of the Protagorean doctrine, as given here by Sokrates is to a great degree just. You cannot explain the facts of consciousness by independent Subject and Object.]