The reasoning of Plato against these opponents is thus open to many of the remarks made by Sir William Hamilton, in the notes to his edition of Reid's works, upon Reid's objections against Locke and Berkeley: Reid restricted the word Sensation to a much narrower meaning than that given to it by Locke and Berkeley. "Berkeley's _Sensation_" (observes S. W. Hamilton) "was equivalent to Reid's _Sensation_ plus _Perception_. This is manifest even by the passages adduced in the text" (note to p. 289). But Reid in his remarks omits to notice this difference in the meaning of the same word. The case is similar with Plato when he refutes those who held the doctrine [Greek: E)pistê/mê = Ai)/sthêsis]. The last-mentioned word, in his construction, includes only a part of the meaning which they attributed to it; but he takes no notice of this verbal difference. Sir William Hamilton remarks, respecting M. Royer Collard's doctrine, which narrows prodigiously the province of Sense,--"_Sense_ he so limits that, if rigorously carried out, no sensible perception, as no consciousness, could be brought to bear". This is exactly true about Plato's doctrine narrowing [Greek: ai)/sthêsis]. See Hamilton's edit. of Reid, Appendix, p. 844. Aristotle understands [Greek: ai)/sthêsis--ai)sthêtikê\ psuchê\] or [Greek: zôê/]--as occupying a larger sphere than that which Plato assigns to them in the Theætêtus. Aristotle recognises the five separate [Greek: ai)sthê/seis], each correlating with and perceiving its [Greek: i)/dion ai)sthêto/n]: he also recognises [Greek: ê( koinê\ ai)/sthêsis]--common sensation or perception--correlating with (or perceiving) [Greek: ta\ koina\ ai)sthêta/], which are _motion_, _rest_, _magnitude_, _figure_, _number_. The [Greek: koinê\ ai)/sthêsis] is not a distinct or sixth sense, apart from the five, but a general power inhering in all of them. He farther recognises [Greek: ai)/sthêsis] as discriminating, judging, comparing, knowing: this characteristic, [Greek: to\ kritoko\n] and [Greek: gnôstiko/n], is common to [Greek: ai)/sthêsis, phantasi/a, no/êsis], and distinguishes them all from appetite--[Greek: to\ o)rektiko/n, kinêtiko/n], &c. See the first and second chapters of the third Book of the Treatise De Animâ, and the Commentary of Simplikius upon that Treatise, especially p. 56, b. Aristotle tells us that all animals [Greek: e)/chei du/namin su/mphuton kritikê/n, ê(\n kalou=sin ai)/sthêsin.] Anal. Poster. ii. p. 99, b. 35. And Sir William Hamilton adopts a similar view, when he remarks, that Judgment is implied in every act of Consciousness.