Two Doctrines of the Mean

Here is the issue. Rosalind Hursthouse, in her contribution to the recent Blackwell anthology on NE, dismisses the Doctrine of the Mean on the grounds that it is a 'whacky' bit of pseudoscience, that has 'no truth in it whatsoever'. She claims that Aristotle unthinkingly applies the doctrine to ethics. Her essay consists largely of an exposition of two other views which she finds in NE and which she thinks are true: (i) that there are various 'parameters' with respect to which we can go wrong in action; (ii) that our emotions make us 'naturally fitted to receive the virtues'.

Hursthouse is very enthusiastic about these other ideas: the first, she says, is 'a great insight into what is required for acting (and feeling)', and the second is 'a wonderful way to think about virtue'. For my part, I'm not clear that (i) is so great an insight, and I'm not even sure what Hursthouse means by (ii).

But I want to look more at Hursthouse's rejection of the Doctrine of the Mean.

As I said yesterday, it's implausible to say, as she does, that Aristotle unthinkingly injects the doctrine into ethics. In NE he is very clear about the impropriety of applying generalizations from natural science to human character, except in some altered or analogous sense. Tellingly, in VIII.8 he deals with the natural scientific doctrine of the mean in just this way and declares that the discussion of it 'belongs to a distinct discipline'! So Aristotle is on record as explicitly rejecting precisely the mistake that Hursthouse attributes to him!

But today I wish to press another difficulty, namely, that the natural scientific doctrine of the mean (as we may call it) is evidently different from the Doctrine of the Mean as stated in the ethics. They are two different notions of an intermediate or mean (meson).

The natural scientific doctrine of the mean, I take it, is something like the following. In a teleological system, it often happens that extremes, or opposites, need to be somehow 'neutralized', in order to make the required contribution to the good of the whole. This neutralization can take place either through a balancing (in which we imagine that the extremes continue to have their force, but in equiposition), or a mixture (in which we imagine that each extreme acts on the other to produce some resultant product that falls in between).

One might regard this doctrine as Aristotle's view about what is right in Heraclitus' view of co-dependent opposites.

Now two points about this.

First, it is not a whacky doctrine at all. Indeed, one might think that something like this must be true, simply given the nature of a teleological system. One might of course doubt that such systems exist (in which case it is 'teleology', and undoubtedly also 'hylomorphism', which one must regard as pseudoscience). But what such a system would be, is a system in which parts that otherwise would not operate together harmoniously, to some single effect, are so adapted that they now do so. This very description requires that its parts somehow be balanced or mutually opposed, so that the effects that each would otherwise produce are moderated.

It would be easy to think of examples of this. Consider for instance how electrical impulses are propagated along the membrane of a nerve cell. The movement of the charge is achieved not by the conduction of electrons within the cell (as in a copper wire), but rather by a change and transmission in potential effected by sodium and potassium ions. As this potential is propagated, the charge at each location is 'neutralized' and effected at the immediately continguous location. Thus the 'extremes' of positive and negative charges are used against each other to achieve safely an effect (the propagation of an electric signal) that might otherwise be hazardous to living tissue. Furthermore, through this neutralization the tissue immediately regenerates its capacity to propagate an impulse. (See for instance the Introduction here.)

The point is that it is natural to speak of living systems, or perhaps even natural systems generally, as 'harnassing' and 'moderating' forces that, operating on their own outside of such systems, would work to an extreme that would be incompatible with the good functioning of such systems. This I take it is what the 'natural scientific doctrine of the mean' is meant to capture.

Put me on record as holding that there is something right about this; it is not 'whacky'.

But, second, this is not the Doctrine of the Mean as used in Aristotle's ethics. I do not see that Aristotle conceives of, or defines, a virtue as consisting of a balance or mixture of opposing forces. What's the evidence that he does? Hursthouse supplies none.