From the Beginning to Plato

FROM THE BEGINNING TO PLATO 123
Parmenides’ philosophical starting-point looks, in this light, rather like that of
Descartes. Both start with a philosophical enquirer, an apparently isolated mind,
trying to establish what it can know with absolute certainty. Parmenides
approaches the problem via the concept of alētheiē, the reality that would have to
underwrite any knowledge. What is next to be examined is his argument to
establish that there must be such a reality. It is here that his further initial
presuppositions, if any, are to be found. This is the argument that rejects the way
that says ‘it is not’.
The Rejection of ‘it is not’
The passage in which Parmenides justifies the rejection of the second way is
probably not preserved entire. There survive, in fact, only the beginning ((A)
below) and the end, plus a single sentence presumably belonging closely with it
((B) below).
(A)…this track, I tell you, is utterly unconvincing [or: undiscoverable]; for
you would not recognize [or; become aware of] what is not (for that cannot
be done), nor would you point it out.
(DK 28 B 2.6–8)
The claim is that the way ‘it is not’ must be rejected. The verbs on which the
argumentative weight is thrown, are, in the aorist forms used here, common
Homeric words for ‘recognize’ and ‘point out’; they are cognitive ‘success
verbs’. Their objects can be either ordinary individuals or ‘that’-clauses. So it is
necessarily true that (1) ‘you would not recognize [to be the case: i.e. get
knowledge of], or point out [as being the case: i.e. show, demonstrate], what is
not’.
The natural way to expand (1) into a relevant argument is as follows. If there
is no such thing as reality, then no-one can recognize it, nor point it out. In that
case there can be no knowledge (if knowledge requires recognition of reality)
and no communication of knowledge.
This will suffice to reject ‘it is not’, provided two further premisses are
available: (2) that knowledge involves or consists in awareness of reality, and
communication of knowledge involves or consists in the pointing-out of reality;
(3) that knowledge and its communication are possible. 11
Did Parmenides supply any support for (2) and (3)? As to (2), there is no way
of telling; maybe it was taken as following immediately from the meaning of
alētheiē, as that which truths are about, and knowledge is of. As to (3), first of all
some evidence of Aristotle comes in here opportunely. Aristotle identifies, as an
underlying thesis of the Eleatics, that ‘some knowledge or understanding
(phronēsis) is possible’ (Aristotle, On the Heavens III. 1, 298b14–24). This
supports the reconstruction; but does not tell what grounds if any were given for
(3). It cannot be that this assumption is embodied in the initial acceptance of the