To: Katherine A.
From: Geoffrey Klempner
Subject: Heraclitus: we never step into the same river twice
Date: 25 April 2007 11:28

Dear Katherine,

Thank you for your email of 19 April, with your second essay for the Ancient Philosophy program, in response to the question, ''Upon those that step into the same rivers different and different waters flow... they scatter and... gather... come together and flow away... approach and depart'. - What did Heraclitus mean by his famous assertion that we never step into the same river twice?'

I don't normally quote from letters I have written to other students, but in this case was taken aback by the coincidence. This morning, I was commenting on an essay by Stuart, one of my students who is taking the BA in Philosophy via the University of London External programme. Stuart is retired, and lives in Canada. The question, set by the UoL examiner, was, 'The ordering, the same for all, no god or man has made, but it was, is and will be: fire ever-living, being kindled in measures and going out in measures.' (Heraclitus fr. 30.) Discuss.'

Here are the crucial bits from my email to Stuart:

'... There is a lot of philosophical meat in the issue over the traditional view of omnipresent flux and the view preferred by a number of recent commentators including Kirk and Raven that all Heraclitus was saying is that all things are in a process of change but 'not all at once' [...]

'According to Kirk and Raven, on Heraclitus' theory some things change rapidly, while other things change very slowly. If we were to look very closely at a rock, for example, we would see that the rock was undergoing a process which, over a few thousand or hundred thousand years would produce a visible change. In other words, in this world, nothing is immutable. But how does that contribute to the on-going debate? Thales or Anaximander or Anaximenes could have said the same [...]

'Heraclitus thought that he was putting forward a radical proposal which few mortals were equipped to grasp. The alternative interpretation just doesn't seem radical enough.'

- As you can see, I totally agree with you that Heraclitus thought that what he had to say was 'radical and extremely important'.

The first point that needs to be discussed is the question of what it means to say that 'X changes', for any entity X. In language, we have nouns and proper names which refer to objects. 'Katherine', 'the tree outside my window', 'Canada', 'the Milky Way' and so on. As a matter of logic, the possibility of names for things implies a distinction between the 'essential' and 'accidental' properties of a thing. The essential properties are such that, if they were to be lost, we would say that the entity in question no longer 'exists'. For example, it is an accidental, and not an essential property of the tree outside my window that the blossom has come out. By contrast, if the tree was cut down and the wood used to make a shed, we would say that the tree no longer exists, even though its wood survives.

The Presocratic philosophers were struggling to understand the logic of change. The question they asked themselves was whether there was anything constant which remains in existence when an object ceases to exist. For example, the tree. But wood can be burned. Then all that is left is smoke and ash. Is there *something*, perhaps something we can't directly see, which remains in existence when the tree is transformed into a shed and the shed is transformed into ash?

Modern science has an answer in the theory of molecules, atoms and subatomic particles. Thales and Anaximenes seem to be putting forward a similar 'physical' theory in claiming that the ultimate 'stuff' is water (this is controversial in the case of Thales, who may have just meant that all things come from water) or, in the case of Anaximenes, air.

By contrast, the view of Heraclitus is that there is no ultimate stuff. He is not saying that things are 'made of' fire in the sense that Anaximenes said that things are made of air. Things change, according to Heraclitus, but there is no ultimate 'stuff', no ultimate 'subject' of change. The only thing that continues is the Logos, the law of change.

That is radical. Other philosophers recognized the 'impermanence of things', but only Heraclitus took this thought to the extreme of denying that there is any underlying substrate behind the changes.

From the point of view of logic this raises very difficult issues. Language cannot even get going unless we identify 'subjects' to which we attribute various 'properties', like the blossoming tree. So Heraclitus is led to question the very nature of language itself. On the view of total flux, the words that we apply, like 'river' or 'rock' are merely conventional labels for patterns of change. The underlying reality of flux cannot be literally described, but can only be conveyed in similes and metaphors.

It is therefore no accident that Heraclitus was driven to speak in 'riddles'. We cannot 'see' or 'describe' a world where there are no objects, only processes. Logic forces us to speak as if there were permanent 'things' or a permanent 'stuff' underlying the changes that we do see. But this logic, Heraclitus ardently believed, is ultimately misleading as a guide to the nature of ultimate reality.

All the best,

Geoffrey