Plato had assiduously labored at the solution of this problem. The object of his dialectic was "to lead upward the soul to the knowledge of real being," [591] and the conclusions to which he attained may be summed up as follows:
1st. Beneath all SENSIBLE phenomena there is an unchangeable subject-matter, the mysterious substratum of the world of sense, which he calls the receptacle (ἱποδοχή) the nurse (τιθήνη) of all that is produced. [592]
It is this "substratum or physical groundwork" which gives a reality and definiteness to the evanescent phantoms of sense, for, in their ceaseless change, they can not justify any title whatever. It alone can be styled "this" or "that" (τόδε or τοῦτο); they rise no higher than "of such kind" or " of what kind or quality" (τοιοῦτον or ὁποιονοῦν τι). [593] It is not earth, or air, or fire, or water, but "an invisible species and formless universal receiver, which, in the most obscure way, receives the immanence of the intelligible." [594] And in relation to the other two principles (i.e., ideas and objects of sense), "it is the mother" to the father and the offspring. [595] But perhaps the most remarkable passage is that in which he seems to identify it with pure space, which, "itself imperishable, furnishes a seat (ἕδραν) to all that is produced, not apprehensible by direct perception, but caught by a certain spurious reasoning, scarcely admissible, but which we see as in a dream; gaining it by that judgment which pronounces it necessary that all which is, be somewhere, and occupy a certain space." [596] This, it will be seen, approaches the Cartesian doctrine, which resolves matter into simple extension. [597]
[Footnote 591: ][ (return) ] "Republic," bk. vii. ch. xii. and xiii.
[Footnote 592: ][ (return) ] "Timæus," ch. xxii.
[Footnote 593: ][ (return) ] "Timæus," ch. xxiii.
[Footnote 594: ][ (return) ] Ibid., ch. xxiv.
[Footnote 595: ][ (return) ] Ibid., ch. xxiv.
[Footnote 596: ][ (return) ] Ibid., ch. xxvi.
[Footnote 597: ][ (return) ] Butler's "Lectures on Ancient Philosophy," vol. ii. p. 171.