Body and Soul in Ancient Philosophy

Heraclitus on measure and the explicit emergence
of rationality
Anthony A. Long
Heraclitus made remarkable contributions to the idea and the ideal of rationality.
In particular, he prefigured many of the distinctive ways by
which Plato and subsequent Greek philosophers conceptualized this cardinal
notion. These are the two propositions I intend to substantiate in
my paper. No one, I presume, needs to be persuaded that Heraclitus’
logos involves rationality in some sense or senses of that word. 1 The interest
of the inquiry turns entirely on what Heraclitus himself was seeking
to express with the term logos and on why, in recounting his own
logos, he uses such words as metron, nomos, harmoniÞ, kosmos, dikÞ,
This paper began its life as a contribution to the discussions of Heraclitus which
took place in the summer of 2005 at Kusadasi as part of the Symposium Philosophiae
Antiquae Quintum, organized by Apostolos Pierris. I am most grateful for
his invitation to participate and also to Dorothea Frede for giving me the further
opportunity to present my views at the Hamburg conference on Leib und Seele
in der antiken Philosophie. I thank the conference participants for their responses
and also Andrea Nightingale and Chiara Robbiano, who sent me written comments
on the paper. A version of it is also due to appear in the proceedings of
the Symposium Philosophiae Antiquae Quintum, edited by Apostolos Pierris.
1 I intend this generalization to encompass both the minimalist interpretations of
logos, favoured by West 1971, 124–129, and Barnes 1981, 59 (for whom logos is
simply Heraclitus’ account, without metaphysical and theological connotations)
and interpretations represented by Kirk 1962, 65 – 71, 188 – 189, which take the
term’s referents to include divine law. I side with Kirk (see Long 1996a, 47 – 51)
in thinking that Heraclitus adumbrated the Stoic conception of a universal causal
principle, which is not to say that he anticipated their notion of a benevolently
designing and ruling deity. Actually, even Barnes (ad loc.) allows that Heraclitus
B 1 “makes it clear that his ‘account’ must include or embody something
like a general ‘law of nature’”. From the copious literature, I select the following
as particularly helpful programmatic statements concerning the Heraclitean
logos: Kahn 1979, 102, “rationality as a phenomenal property manifested in intelligent
behaviour”, and Hussey 1999, 93, who says of the “authority that the
logos enjoys … It can be none other than the impersonal kind of authority that is
intrinsic to reason or rationality”. See also Dilcher 1995 ch. 2.