“[The soul is an exhalation that perceives; it is different from the body, and always flowing.]” (K, 113; cp. D A15 and D 12)
The fragment provided here is not found in Robinson, Sweet, or others, who only provide the texts Diels and Kranz originally classified as clear quotes (the texts denoted as “B” in their work). This fragment is taken from the “Testamonia” — views attributed to Heraclitus by others in their commentaries and noted by Diels and Kranz with the “A” numbering (here A15). This fragment is taken from Cleanthes and Aristotle. The idea, found in Aristotle’s account, that for Heraclitus the soul is “always flowing” is also included, in Cleanthes’ text, which is rendered completely here in Fragment 50 (D 12): “As they step into the same rivers, others and still others waters flow upon them” (see Kahn, pp. 259). This longer quote is only part of what is provided in Cleanthes’ text.
The soul is here compared, in the diverse sources, with air (as exhalation) but also with water (as always flowing). It allows perception. Yet it is not identified with the body. A body, without soul, would be a mere corpse, which as Heraclitus has said “should be thrown out quicker than dung” (F 88 [D 96]).