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Milesian primary substance and the river of Heraclitus


To: Harri K.
From: Geoffrey Klempner
Subject: Milesian primary substance and the river of Heraclitus
Date: 10th March 2010 14:22

Dear Harri,

Thank you for your email of 28 February, with your essay for the University of London BA Plato and the Presocratics module, in response to the question, ''Examining the theories of the Milesian philosophers concerning the nature of the primary substance, we find a progressive clarification of the questions asked, and an improvement in the answers given to those questions.' Discuss', and your email of 7 March, with your essay 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 am flattered that in both cases you have chosen to answer questions from the Pathways Presocratics question sheet rather than tackle University of London examination questions! When I composed these questions, I still had dim memories of the lectures I attended on the Presocratics, given by Professor David Hamlyn, who was then (1972-3) Head of Department of Birkbeck College London.


There is a danger here that you have tried to answer two questions, not only the question about the theories concerning the nature of the primary substance but also the different question of the relation between 'mythos' and 'logos'. The first question starts strictly at the point where the transition from mythos to logos has been achieved -- regardless of one's views, e.g. about how sharp a transition this is, or whether we can view earlier mythical accounts as proto-scientific 'theories' (hence a Kuhnian 'paradigm shift'). That's all water under the bridge (pardon the pun) so far as the Milesians are concerned.

The question clearly refers to two distinct issues: the 'progressive clarification of questions' asked is the first issue, while the 'improvements in the answers' is the second issue. It was not clear to me from what you wrote exactly what you think the 'question asked' is for Thales, Anaximander and Anaximenes.

Here are some possible questions: Where does the universe come from? What are things made of? How is change possible? Why does the world which we observe show such order and regularity?

Well obviously, question 2 is a dead give-away. But why ask this question? Why would you ever think that 'things' are 'made' of something in particular, rather than just what they are (trees are made of wood, pots are made of clay, bone is made of bone etc. etc.) So although it is arguably true that the idea that 'everything is water' creates the logical space for the idea of a 'scientific theory' of the world in the modern sense, it seems an incredible leap to have formulated this idea in the first place.

In what way was there a 'progressive clarification' in the questions asked? You don't say. You state the reasons why Apeiron was regarded as an improvement on water, and why air was an improvement on Apeiron and not a step backwards --because Anaximenes combined this with his novel theory of condensation and rarefaction -- but it is still not clear whether all three philosophers where asking the same question, or whether they improved on the question as well as on the answer.

Here, you could have pointed out that both Anaximander and Anaximenes introduce the idea of lawlikeness, the first explicitly in the quote 'they pay reparation for their injustice according to time' and the second implicitly in the rarefaction-condensation theory (when you compress air it 'always' goes cold, and not sometimes hot and sometimes cold -- we know this is wrong, based on insufficient observation but that's irrelevant so far as this point about clarification of the question is concerned).

Then again, Anaximenes clearly develops the question raised about lawlikeness precisely because he asks, 'what is the mechanism?' which is a very modern idea. By contrast, Thales with his talk of 'all things are full of gods' seems to have one foot still in the mythological camp.

So, in summary, if this was an answer to an examination question, you would have done better to cut the discussion of mythos and logos, and expand on the distinction between 'improving the question' and 'improving the answer to a given question'.


I can see that you are clearly excited by this question about Heraclitus. Let's look at the case of the river first, as you do, because a number of issues arise out of it.

Does a river need a riverbed? No. Let's say I forget to turn the tap off when filling the bath and when I get to the bathroom, there is a 'river' of hot water running down the side of the bath. Not a sheet of water but a clearly identifiable stream which changes from moment to moment but nevertheless maintains a characteristic shape. That's one of the interesting properties of water. Another liquid which had lower surface tension would behave in a different way.

What is constant, despite the changing water and changing shape is something you can define mathematically. It is a curvy line, not a plane (sheet) or a 'tree' (i.e. a stream which 'forks' into two streams etc.)

What this shows (to me, at any rate) is that you can have a kind of 'identity' which depends solely on geometrical properties. When I referred to 'surface tension' I was alluding to an underlying physical explanation for why water behaves in the way that it does and differently from some other liquids, but the idea of the availability of an underlying physical explanation is not part of Heraclitus' theory (although it was part of the Greek atomist view).

Imagine as you are sitting by a log fire, ball-shaped fiery 'objects' emerge and dance around the room, scorching the furniture. Their 'bodies' are clearly visible. We know this doesn't happen in real life, but in essence their 'identity' is based on the same principle as the river. (I just remembered however, the rare phenomenon of 'ball' lightning.)

Is a characteristic identifiable shape alone sufficient for 'identity'? It is, if you have an underlying principle, such as the logos. I think that you have seen this point. A consequence is that there is a logically possible Heraclitean world where fire 'creatures' do indeed exist, and the explanation for their existence is given by the logos, just as the logos explains all the other things in existence.

The link to Plato and also Aristotle is apparent: there are 'forms' (such as the form of horse or the form of a river) and the fact that we encounter different kinds of spatio-temporal particular is explained by the existence of these forms.

You missed one important thing that Heraclitus says about the logos, which fills in a vital part of the picture. Souls can be 'wet' or 'fiery'. The logos refers to a universal order, but at the same time each of us is (or has) this ordering principle in ourselves. Again, the link with Plato is apparent, in the 'affinity' between the soul and the Forms. What Plato would term an 'ordered' soul (Republic) is in Heraclitean terms fiery rather than wet.

Heraclitus is not just concerned with the question of identity through change. We know that some things change very slowly. I would be very affronted if you told me, a Londoner (by birth) that the Thames is not a river. But in point of fact, there are times when the tide is changing, when the Thames does not 'flow' in any direction but remains static.

Yet for Heraclitus, as you observe, stasis is equivalent to death. The fire, the flowing river, exist only because they are changing. Then what about the Thames, or a rock for that matter?

Here, there are different views depending on whether or not you take a Platonic view of Heraclitus. For Plato, the world of phenomena is a world where there is no stasis, nothing is permanent. The apparent relative permanence of the rock is explained in exactly the same way as one would explain the relative permanence of a river or a fire. Reality is a process, which generates identifiable spatio-temporal particulars as the result of a law or principle (the forms or the logos).

A more modern view is that Heraclitus was not so extreme as to hold that a rock 'flows' like a river. On the contrary, he is perfectly happy to admit that, while all things change, rocks change only very slowly. I'm not convinced by this attempt to 'domesticate' Heraclitus. I prefer the wilder version.

All the best,