CHAPTER SIX

CONCLUSION

Even the bare outlines of Speusippus' metaphysical, epistemolo­ gical, and ethical doctrines given in chapters two, three, and four of this work show that he was a philosopher of considerable original­ ity.473 In view of this and of the likelihood that Plato himself chose him to be his successor as head of the Academy,474 it is surely unwarranted and arbitrary to contend, as some scholars do, 476 that he was a poor philosopher. It is clear that Plato was the main influence upon Speusippus' thought. For his most important metaphysical and epistemological doctrines show not only that he adopted some of the basic tenets of Platonism but also that these doctrines are answers to the same problems Plato tried to solve. Thus, take for example Speusippus' doctrine that numbers and magnitudes are separate, eternal, and immutable objects of knowledge; that mathematical numbers are directly apprehended by the mind; that the propositions of mathematics cannot be true of the sensibles; that by the direct knowledge of number together with the data provided by an infallible faculty of perception which participates in reason the mind is able to derive all other knowledge; and that there is a relation of non-symmetrical similarity between the several kinds of substances which ultimately depends upon the separately existing numbers. All these interrelated doctrines are not only similar to some of Plato's own but are really answers to the same kinds of problems which Plato's philosophy tries to solve. For Plato's own main doctrines-the theory of ideas, the conception of the soul as a perpetual entity to which the apprehen­ sion of the ideas is so to say "innate," knowledge as recollection, etc.-were meant as an answer to the question whether there is such a thing as knowledge which is fundamentally different from perception and correct opinion. If there is, as Plato thought there is, then for him there must be a soul with the power to apprehend

478 For Speusippus' main doctrines and for his relation to Plato's the reader is referred to Chs. II-IV supra. 474 Cf. pp. 8-u supra. 476 Cf. note 32 supra. CONCLUSION rog the objects of knowledge, these objects must themselves be eternal and immutable entities outside of time and space, and phenomenal existence must imitate, or participate in, the eternal entities called ideas.476 Speusippus' main doctrines, then, are not only similar to Plato's but are also a different answer to the same problems which presuppose some of Plato's own central beliefs: that the mind apprehends eternal and unchangeable entities which exist apart from the sensibles, that the human soul is endowed with a faculty (mind) capable of such apprehension, and that there must be some kind of direct knowledge. And even Speusippus' bond of similarity among his several kinds of substances is but a modifica­ tion of Plato's fundamental assumption that phenomena imitate, or participate in, the eternally existing objects of knowledge. The reconstruction of the reasons why Speusippus modified Plato's theory is discussed in chapters two and three, and so we need not pursue this topic here. There is some evidence that Speusippus pointed out the similarity of his doctrine to certain Pythagorean tenets. 477 It is intelligible why he did so, for he probably saw in the early Pythagorean notion that everything is but number an antecedent of his own belief that numbers are the first entities. Our evidence indicates that he used some early Pythagorean tenets in order to put forward his own doctrines. But, even in this last case, what is significant is that he uses the Pythagorean doctrines in question for his own purposes, not simply to report them; and his own doctrines are essentially at variance and often incompatible with those of the early Pythagoreans. Nor is there any reason to think that Speusip­ pus invariably referred to the Pythagoreans as his predecessors. The widespread notion that he did so is unwarranted; and that his philosophy is indebted to them in essentials is contradicted by all the pertinent information we have, including the testimony of Aristotle.478 The extant evidence points to an unmistakable fact: that Speus­ ippus' thought exercised a considerable influence upon Aristotle

478 Cf. esp. pp. 13 and 70-71 supra and Cherniss, "The Philosophical Economy of the Theory of Ideas," AJP 57 (1936), pp. 445-456 = Selected Papers, pp. 121-132. 477 On Speusippus and the Pythagoreans cf. note 415 supra. 478 On this last point cf. esp. p. 71 supra and comm. on F 33, F 38, line 1, F 50-52, F 62 with note 202.