[Footnote 86: Ibid. b. 35: [Greek: dê=lon o(/ti kai\ ei) ê)=n ai)stha/nesthai to\ tri/gônon o(/ti dusi\n o)rthai=s i)/sas e)/chei ta\s gôni/as, e)zêtou=men a)\n a)po/deixin, kai\ ou)ch (_ô(/sper phasi/ tines_) ê)pista/metha; ai)stha/nesthai me\n ga\r a)na/gkê kath' e(/kaston, ê( d' e)pistê/mê tô=| to\ katho/lou gnôri/zein e)sti/n.] Euclid, in the 20th Proposition of his first Book, demonstrates that any two sides of a triangle are together greater than the third side. According to Proklus, the Epikureans derided the demonstration of such a point as absurd; and it seems that some contemporaries of Aristotle argued in a similar way, judging by the phrase [Greek: ô(/sper phasi/ tines].] [Footnote 87: Analyt. Post. I. xxxi. p. 88, a. 2: [Greek: ou) mê\n a)ll' e)k tou= theôrei=n tou=to polla/kis sumbai=non, to\ katho/lou a)\n thêreu/santes a)po/deixin ei)/chomen; e)k ga\r tô=n kath' e(/kasta pleio/nôn to\ katho/lou dê=lon.] Themistius, p. 62, Sp.: [Greek: a)rchê\ me\n ga\r a)podei/xeôs ai)/sthêsis, kai\ to\ katho/lou e)nnoou=men dia\ to\ polla/kis ai)sthe/sthai.]] [Footnote 88: Analyt. Post. I. xxxi. p. 88, a. 6: [Greek: to\ de\ katho/lou ti/mion, o(/ti dêloi= to\ ai)/tion; ô(/ste peri\ tô=n toiou/tôn ê( katho/lou timiôte/ra tô=n ai)sthê/seôn kai\ tê=s noê/seôs, o(/sôn e(/teron to\ ai)/tion; peri\ de\ tô=n prô/tôn a)/llos lo/gos.] By [Greek: ta\ prô=ta], he means the [Greek: a)rchai\] of Demonstration, which are treated especially in II. xix. See Biese, Die Philos. des Aristoteles, p. 277.] [Footnote 89: Analyt. Post. I. xxxi. p. 88, a. 9-17. [Greek: e)/sti me/ntoi e)/nia a)nago/mena ei)s ai)sthê/seôs e)/kleipsin e)n toi=s problê/masin; e)/nia ga\r ei) e(ô/rômen, ou)k a)\n e)zêtou=men, ou)ch ô(s ei)do/tes tô=| o(ra=|n, a)ll' ô(s e)/chontes to\ katho/lou e)k tou= o(ra=|n.] The text of this and the succeeding words seems open to doubt, as well as that of Themistius (p. 63). Waitz in his note (p. 374) explains the meaning clearly:--"non ita quidem ut ipsa sensuum perceptio scientiam afferat; sed ita ut quod in singulis accidere videamus, idem etiam in omnibus accidere coniicientes universe intelligamus."] Aristotle next proceeds to refute, at some length, the supposition, that the _principia_ of all syllogisms are the same. We see at once that this cannot be so, because some syllogisms are true, others false. But, besides, though there are indeed a few Axioms essential to the process of demonstration, and the same in all syllogisms, yet these are not sufficient of themselves for demonstration. There must farther be other premisses or matters of evidence--propositions immediately true (or established by prior demonstrations) belonging to each branch of Science specially, as distinguished from the others. Our demonstration relates _to_ these special matters or premisses, though it is accomplished _out of_ or by means of the common Axioms.[90]