必然ということ : 「チマイオス」解釋の一斷面

Abstract

What does Plato mean by the word "Necessity", when he makes Timaeus say that Reason (νοûς) must over-rule Necessity (àνάγκη), an errant cause, in order to fashion this universe? We can hardly follow Archer-Hind in his identification of Necessity with natural law. For, as Taylor says, Necessity ought to be taken as the very antithesis of Reason which is the cause of rationality or regularity. Are there, then, any irrational or irregular elements in Timaeus's world, which come about of Necessity? (Supposing that we were provided with complete knowledge, Necessity, Taylor holds, would "vanish from our account of the world." But Cornford objects to this utterance on the ground that Greek god or gods are not omnipotent, and that Necessity, which is not completely subdued by Reason, is, therefore, not a mere illusion, but a cause which is actually at work.) Are there, then, as Grote or Cornford maintains, any indeterminate, inconstant, anomalous elements in Timaeus's world? But again, how can such Necessity be related to that in Leucippus's words : "Nothing occurs at random; everything occurs from a reason (λόγος) and by necessity" : or to that inexorable figure of Ananke in the myth of Er? This article is an attempt to answer these questions from the author's point of view which consists in searching for the meaning of reason (λόγος) and its antithesis. The conclusions are as follows : (1) one of the characteristics of "àνάγκη" is that it is indifferent to human or reasonable purposes, rather than irregular or indeterminate ; (2) the mere mechanical movements of four elements or atoms are to be described as having been "caused by necessity", in so far as they are independent of and indifferent to the reasonable purpose, though they may be determined by the preceding conditions ; and (3) Plato aims at setting, against Necessity, one higher cause, Reason, which works with a purpose, and also at showing that the latter is conquered to become an auxiliary means to the former's end.