From the Beginning to Plato

FROM THE BEGINNING TO PLATO 127
The ‘signs’ are best taken as the proofs, to follow, of the properties announced
here as belonging to ‘what is’ (eon), i.e. reality. Evidently the deduction of the
consequences of ‘it is’ constitutes, as expected, the journey along the way.
(a)
Reality cannot come-to-be nor cease-to-be (B 8.6–21)
For, what origin will you seek for it? How and from where did it
grow? Nor will I let you say or think that [it did so] out of what is
not, for it is not sayable or thinkable that it is not. Besides, what
necessity would have driven it on to come-to-be, later or sooner,
starting from what is not?
(DK 28 B 8.6–10)
The first section of proof reveals the techniques of argument characteristic of this
part. For convenience, the subject (‘what is’ or ‘reality’) will be denoted by E.
Suppose that E does at some time come-to-be. Then Parmenides asks: out of what
does it come-to-be? The implied premiss is: (10) whatever comes-to-be, comesto-be
out of something. Parmenides seems to have taken (10) as self-evidently
true; it is plausible to connect it with other places in this argument where he
seems to have some variety of the Principle of Sufficient Reason in mind.
So, if E comes-to-be, it comes-to-be out of F (say). Then for F, in turn, there are
the two possibilities: F is, or F is not. Parmenides considers the second
possibility, but not, apparently, the first one. This is a first problem.
There is an extra twist to it. So far, we have considered Parmenides’ reasonings
about ‘it is’ and ‘it is not’ without taking account of the ambiguities of the
present tense. The rejection of the way ‘it is not’ does not call for these to be
considered. But the Greek present tense is ambiguous in the same ways as the
English one; and where, as here, possible past and future events are being
discussed, it becomes necessary to distinguish the various uses. ‘It is’ and ‘it is
not’ may be timeless, or refer to the time of the coming-to-be, or to the time of
utterance, if that is different. Parmenides gives us no help at all on this point; but
it is plausible to assume that he means the question ‘is F or is it not?’ to be
understood as specialized (in line with ordinary usage) to the time of coming-tobe.
This results, as will now be shown, in an intelligible argument.
The question is then: E comes-to-be out of F; is F, or is it not, at the time of
E’s coming-to-be? First, if F is, at that time, then at that time it is part of E, since
E (on the interpretation followed here) is the whole of reality. But nothing can
come-to-be out of a part of itself, since that does not count as coming-to-be at
all. This point will account for Parmenides’ failure to examine the supposition ‘F
is’.
Second, suppose then that F, at the time of E’s coming-to-be, is not. This is
the case which Parmenides examines. He gives two arguments.