[p. 339]
Heraclitus, was fully developed in one direction by
Protagoras, who regarded knowledge as conditioned
by (i. e. relative to) the percipient being. In
Nutriment relativity is made to apply, not merely to
the knowledge of properties, but to the properties
themselves. Such an extension of the doctrine
would probably be made somewhat later than the
time of Protagoras, and we may with some confidence
suppose that the author wrote about 400 B.C.
The first chapter of Nutriment distinguishes γένος2
from εἶδος2 after the Aristotelian manner. A similar
distinction occurs in the Parmenides of Plato, and it
need not prevent us from assigning a date as early as
the end of the fifth century B.C.
In Chapter XLVIII mention is made of pulses,
supposed to be the first occasion of such mention in
Greek literature.
See Sir Clifford Allbutt, Greek Medicine in
Rome, Chapter
XIII, for the ancient doctrines about pulses. It is most
remarkable that before about 340 B.C. their great importance
was not realised. |
This fact, again, is no argument
against an early date. The reference is quite
general, and amounts to no more than the knowledge,
to be found in several places in the Hippocratic
Corpus,See Littré's index, s.v. battements.
|
that
violent pulsations (of the
temples and so forth) are characteristic of certain
acute diseases.
It should be noticed that the doctrine of δύναμις2
described above is inconsistent with a post-Aristotelian
date. Aristotle's doctrine is obviously a
development of it, and it is clear how the earlier
doctrine prepares the way for the later.
The Heraclitean love of anthithesis results in