EARLY GREEK THINKING
Now these are precisely the words in reference to which Theophrastus complains that Anaximander speaks in a rather poetic manner. Since thinking through this entire question, which came up often in my lecture courses a few years ago, I am inclined to accept only these as the immediate, genuine words of Anaximander, with the proviso however that the preceding parts of the text are not simply set aside, but rather are positively retained, on the basis of the strength and eloquence of their thought, as secondary testimony concerning Anaximander's thinking. This demands that we understand precisely these words γένεσις and φθορά as they are thought in Creek, whether they be preconceptual words or Platonic-Aristotelian conceptual terms.
Accordingly, γένεσις does not at all mean the genetic in the sense of the "developmental" as conceived in modem times; nor does φθορά mean the counterphenomenon to development—some sort of regression, shrinkage, or wasting away. Rather, γένεσις and φθορά are to be thought from φύσις and within it, as ways of luminous rising and decline. Certainly we can translate γένεσις as origination; but we must think this originating as a movement which lets every emerging being abandon concealment and go forward into unconcealment. Certainly we can translate φθορά as passing away; but we must think this passing away as a going which in its turn abandons unconcealment, departing and withdrawing into concealment.
Presumably, Anaximander spoke of γένεσις and φθορά It remains questionable whether this occurred in the form of the traditional statement, although such paradoxical turns of speech as γένεσις ἔστιν (which is the way I should like to read it) and φθορά γίνεται, "coming-to-be is," and "passing-away comes to be" still may speak in favor of an ancient language. Γένεσις is coming forward and arriving in unconcealment. Φθορά means the departure and descent into concealment of what has arrived there out of unconcealment. The coming forward into ... and the departure to ... become present within unconcealment between what is concealed and what is unconcealed. They initiate the arrival and departure of whatever has arrived.
Anaximander must have spoken of what is designated in γένεσις and φθορά whether he actually mentioned τὰ ὄντα. remains an open