[Footnote 52: Ibid. b. 36; p. 7, a. 5. [Greek: ou) mê\n a)ll' e)ni/ote ou) do/xei a)ntistre/phein, e)a\n mê\ oi)kei/ôs pro\s o(\ le/getai a)podothê=|, a)lla\ diama/rtê| o( a)podidou/s, oi(=on to\ ptero\n e)a\n a)podothê=| o)/rnithos, ou)k a)ntistre/phei o)/rnis pterou=; ou) ga\r oi)kei/ôs to\ prô=ton a)pode/dotai ptero\n o)/rnithos; ou) ga\r ê(=| o)/rnis, tau/tê| to\ ptero\n au)tou= le/getai, a)ll' ê(=| pterôto/n e)sti; pollô=n ga\r kai\ a)/llôn ptera/ e)stin, a(\ ou)k ei)si\n o)/rnithes.]] [Footnote 53: Ibid. p. 7, a. 6-25. [Greek: e)ni/ote de\ kai\ o)nomatopoiei=n I)/sôs a)nagkai=on, e)a\n mê\ kei/menon ê)=| o)/noma pro\s o(\ oi)kei/ôs a)\n a)podothei/ê], &c.] The _Relatum_ and its Correlate seem to be _simul naturâ_. If you suppress either one of the pair, the other vanishes along with it. Aristotle appears to think, however, that there are many cases in which this is not true. He says that there can be no _cognoscens_ without a _cognoscibile_, nor any _percipiens_ without a _percipibile_; but that there may be _cognoscibile_ without any _cognoscens_, and _percipibile_ without any _percipiens_. He says that [Greek: to\ ai)sthêto\n] exists [Greek: pro\ tou= ai)/sthêsin ei)=nai].[54] Whether any Essence or Substance can be a _Relatum_ or not, he is puzzled to say; he seems to think that the Second Essence may be, but that the First Essence cannot be so. He concludes, however, by admitting that the question is one of doubt and difficulty.[55] [Footnote 54: Ibid. b. 15; p. 8, a. 12. The Scholion of Simplikius on this point (p. 65, a. 16, b. 18, Br.) is instructive. He gives his own opinion, and that of some preceding commentators, adverse to Aristotle. He says that [Greek: e)pistê/mê] and [Greek: to\ e)pistêto/n, ai)sthêsis] and [Greek: to\ ai)sthêto/n], are not properly correlates. The actual correlates with the actual, the potential with the potential. Now, in the above pairs, [Greek: to\ e)pistêto\n] and [Greek: to\ ai)sthêto\n] are potentials, while [Greek: **e)pistê/mê] and [Greek: ai)/sthêsis] are actuals; therefore it is correct to say that [Greek: to\ e)pistêto\n] and [Greek: to\ ai)sthêto\n] will not cease to exist if you take away [Greek: e)pistê/mê] and [Greek: ai)/sthêsis]. But the real and proper correlate to [Greek: to\ e)pistêto\n] would be [Greek: to\ e)pistêmoniko/n]: the proper correlate to [Greek: to\ ai)sthêto\n] would be [Greek: to\ ai)sthêtiko\n]. And when we take these two latter pairs, it is perfectly correct to say, [Greek: sunanairei= tau=ta a)/llêla]. In the treatise, De Partibus Animalium, i. p. 641, b. 2, where Aristotle makes [Greek: nou=s] correlate with [Greek: ta\ noêta/], we must understand [Greek: nou=s] as equivalent to [Greek: to\ noêtiko/n], and as different from [Greek: ê( no/êsis].] [Footnote 55: Aristot. Categ. p. 8, b. 22.]