Of the six to eight essays on Aristotle that Eliot wrote for Joachim during the 1915 Trinity term, [Change in Aristotle’s De generatione et corruptione] is the last of four to have survived.
γένεσις is one of the two species of μεταβολή, of which the other species is κίνησις. 2 The specific difference between γένεσις and the three kinds of κίνησις together is this, that in all κίνησις there is a permanent substratum, a σύνολον 3 (with one exception) of form and matter, which remains the same throughout the change. In any change of quality (τὰ πάθη τῶν ἀπτῶν), 4 one can actually point to the thing which becomes hot or cold, white or black; in any change of place, the object can (perhaps) be handled and observed to be the same; in any change of size, an identity is recognised by perception. But γένεσις or φθορά 5 is thoroughgoing change, almost in the Bergsonian sense. While (in modern terms) κίνησις involves only external relations, in γένεσις a complete alteration of the εἶδος takes place.
This distinction, so clear in principle, is with great difficulty preserved in application. It is impossible, and indeed a priori impossible, to set one’s finger upon an instance where γένεσις is to be observed separable from some other kind of change. For whenever a change is observable, an αἰσθητὸν ὑποκείμενον 6 is present, and γένεσις is that kind of change which takes place when we confess a gap: where we apprehend an identity, but are unable to trace a process. Where are γενέσεις to be found? ἄνθρωπος ἄνθρωπον γεννᾷ. 7 It does not matter whether we assume that the γένεσις was instantaneous or occupied a period of time: it does not matter, that is, whether we find a moment without the phenomenon of αὔξησις or of ϕορά, 8 of nutrition or of the combination of particles. There is a novelty– thisman–the existence of which neither spatial movement nor nutrition is adequate to explain. This novelty is γένεσις.
Aristotle insists that this γένεσις is never actually the production of something out of nothing–an hypothesis exceedingly offensive to reason, but indeed so far as there is γένεσις at all, this is what it is. There is always a continuity of material, and what such continuity amounts to is a continuity of appearances. Were there an identityof material, it would be an identity abstractible in thought; but the material in γένεσις is unformed; material, therefore, which is incapable of preserving identity. It will have no character which is not present to perception; and what is present is the continuity of the appearances.
No γένεσις is out of a vacuum; γένεσις is always ἔκ τινος. 9 It is always of a composite–the bronze globe comes into being, but not bronze (at the same γένεσις) or sphericity. But as a matter of fact the coming to be of the bronze sphere is not in the strictest sense a γένεσις, or (if we make γένεσις a matter of degree) it embodies a low degree of generation. If we carve or mold a bull, the motion is in fact φορά of particles of bronze or wood. Aristotle also speaks of a houseas generated. It would seem that Aristotle uses generation in a wider and a narrower sense: the wider sense comprising every case in which a concrete substantive comes into being (the generation, we might almost say, of bacon out of pig), the narrower sense applying only to organic generation and the passing of one element into another. If the concept of γένεσις depended merely on the latter assumption, it would be unimportant; if it were restricted to the former, it would be merely a name for the explicable but unexplained. We are forced to the conclusion that in organic generation we have only a more typical case, or a case in which the concept of γένεσις is of more practical importance than when we handle artefacts or simple changes (the simplest change–change in place); and to the conclusion that in fact the two ultimate concepts of change are γένεσις and κίνησις κατὰ τόπον. 10 Between these two poles every actual change is located: and no change can be found which is not at the same time a γένεσις and...
