[“One cannot step twice into the same river…nor can one twice take hold of mortal substance in a stable condition; for by the quickness and swiftness of its alteration it scatters and gathers–at the same time it endures and dissolves, approaches and departs.”] (Sweet, 91. Cp. Kahn, 51, DK 91)
Compare Robinson, F 91: “(a) [For, according to Heraclitus, it is not possible to step twice into the same river, nor is it possible to touch a mortal substance twice in so far as its state (hexis) is concerned. But, thanks to (the) swiftness and speed of change.] (b) It scatters (things?) and brings (them?) together again. [(or rather, it brings together and lets go neither ‘again’ nor ‘later’ but simultaneously], (it) forms and (it) dissolves, and (it) approaches and departs.”
You can’t step in the same river twice. This is the line for which Heraclitus is most famous. Yet, among his fragments, we nowhere find it as a stand alone statement. It is expressed here, from Plutarch, but as part of longer body of text that contextualize the views about change as part of a general metaphysics. Robinson, like many historical commentators such as Reinhart, have serious questions about whether that first part of this can even rightly be attributed to Heraclitus.
The first statement has been used to read Heraclitus as a proponent of radical change and non-identity. Edward Hussey has argued that Cratylus was likely the first person to formulate the sentence in the well-known form in which it comes down to us, and that, having done this, he formulated his own retort: “You can’t step in the same river once.” For neither you nor the river remain the same. Hussey suggests that this version would have misled Plato and Aristotle, who read Heraclitus more as a philosopher of radical flux than an examination of his entire fragments justify (See Kahn, fn. 198).
The first statement does align with some other fragments (not included in Kahn). Take Robinson’s 49a “We do and do not step in the same rivers: we are and are not.” But questions also surround the authenticity especially of the second half of this fragment (See Robinson pp. 112ff.). And of course, this fragment speaks of a sense in which the river and we are the same.
Plutarch’s comments in the second part of Fragment 51, especially when taken with other statements of Heraclitus about flux, in any case lead to an understanding of the initial statement in ways different from the proponents of the most radical views of flux. At the very least some kind of world whole (a Western sort of rational Tao) appears to have identity. “It scatters and gathers–at the same time it endures and dissolves.” This indicates change wherein something endures. We see here a notion like Hegelian Aufhebung or “sublation.” The focus on at least the identity of a greater whole can be underlined in reference to F 124: “…from all things one and from one all things.”
The second part of Fragment 51 also underlines the regularity of the change. This is of course highlighted when reading this together with other statements on change, already examined. The cold becomes warm, as we saw in the last Fragment (49); the moist, dry. And such change is not arbitrary or without limits. Fragments 44 and 46, as we have seen, also underline the regularity of change in the cosmos. “The sun will not transgress his measure” (F 44). It will move in its daily course with regularity and in it seasonal course from furthest point (of Winter Solstice) to nearest point (Summer Solstice). Other heavenly bodies also follow a regular course of movement (see F 45). There will be continuous change in the movement of the sun and the stars, but this change occurs in accordance with the law of cosmic justice. Fragment 48 states this in a quite law-like form that aligns with the view of the early Stoa: ” There is a certain order and fixed time for the change of the cosmos in accordance with some fated necessity.”
A similar change with regularity is noted in various of Heraclitus’ passages on the transformation of the elements. Fragment 41 makes the point especially well: “Fire lives the death of earth and earth the death of fire; water lives the death of air, earth that of water.” The change of the cosmos occurs as elements undergo change from one into another. The comments on Fragments 39 through 41 highlight this.
Yet, to be sure, there is ample ambiguity in the Fragments that have come down to us about the permanence of the identity especially of particular objects. Might a reading be justified that concludes that the identity of only one substance is really permanent and that change in that occurs with law lawlike regularity?
To be sure, Heraclitus is emphasizing the importance of process over substance. Yet in denying particular identities, one would find oneself in a situation parallel to that of the readings of identity in Buddhism, where while no-self and impermanence of specific individuals are affirmed, the question then arises about whether the skandhas or aggregates remain with identity as substrates, as change occurs at a foundational level among (a) form, (b) sensation, (c) perception, (d) mental activity, and (e) consciousness. In the case of Heraclitus, such a reading would have to maintain the permanence of the elements: fire, water, earth, air, probably also the secondary qualities, coldness, warmth, dryness, moisture.
This most famous passage of Heraclitus involves us in some of the greatest interpretive difficulties regarding his philosophy. The most consistent reading of Heraclitus, however, views him largely as a philosophical precursor to Hegel. We are to understand reality as a diverse yet unified whole in process. Flux occurs within a whole that is rational and law-like and that preserves diversity in unity. Substance generally, as stated in this fragment, “endures and dissolves, approaches and departs,” involved in a rational process of change.