From the Beginning to Plato

FROM THE BEGINNING TO PLATO 343
therefore changed. (2) He cannot accept that intelligence does not belong to
‘what wholly is’. But if intelligence belongs to being, so must life, soul, and
hence change, belong to being.
Now, to determine Plato’s attitude to this criticism, we need to know: Does
Plato accept the Eleatic Stranger’s definition of being?
And to answer this we would need to answer the following question: Is the
notion of being defined in terms of the capacity to act or be acted on being in the
strong sense or the weaker notion applicable to material objects?
The Sophist itself fails to settle these questions. But if we look to later
dialogues where the earlier contrast between being and becoming is reaffirmed, 42
and assume that the Sophist does not represent a temporary detour, then we can
say the following: (1) If the Sophist defines being in the strong sense, then Plato
cannot accept its definition since he later reaffirms that being cannot apply to the
sensible world of becoming. (2) If the Sophist is defining being in the weaker
sense, then Plato could accept it consistently with his contrast between a stronger
notion of being and becoming. For the fact that x is acted on does not, as the
Stranger falsely suggests (248e), entail that x is altered. One example of ‘acting’
and ‘being acted on’ was that if x possesses an attribute F, then F acts on x, and x
is acted on by F. In this sense the Form of Figure ‘acts’ on the Form of
Triangularity, and, according to the Sophist’s doctrine of the communion of
Forms, the Form of Being ‘acts’ on the Form of Difference. Obviously, this does
not entail that Triangularity or Difference change, and the passage ends with the
changelessness of the objects of knowledge reaffirmed (249b-c; cf. Politicus
269d).
If it is said that the vehemence with which the Stranger asserts that motion,
life, mind and wisdom belong to ‘the wholly real’ shows that he is asserting their
being in the strong sense, this is consistent with the earlier Theory of Forms. 43 It
too asserted the existence of Forms of Soul and Life in the Phaedo. 44 The Form
of Motion is casually referred to in Socrates’ outline of his immature Theory of
Forms in the Parmenides (129e), and the Form of Knowledge is mentioned later
in the same dialogue (134a–e; cf. Phaedrus 247d–e). 45
While there is no clear evidence for the suggested alterations in the Theory of
Forms, the Sophist does undeniably contain one new development: for the first
time Plato speaks of Forms participating in other Forms: the ‘communion of
Forms’. Hitherto, Plato was only concerned to give the ontological analysis of
the fact behind a true statement that a subject S is F when S is an individual. But
in many cases—and many cases of the sort that Plato would be particularly
interested in—the subject of a statement asserting that S is F will name a Form.
If the case where S is an individual demands explanation, it is obvious that the
general case likewise demands an explanation. And this Plato provides for the
first time with his doctrine of the communion of Forms.
A central passage in the Sophist (251a–257a) presents a series of arguments to
distinguish five ‘greatest Kinds’: Being, Sameness, Difference, Rest and Motion.
Many have found more sophisticated theories here, but I believe that communion