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Mill's proof of the utility principle


To: Stuart B.
From: Geoffrey Klempner
Subject: Mill's proof of the utility principle
Date: 13th April 2011 12:31

Dear Stuart,

Thank you for your email of 3 April, with your essay for the University of London BA Ethics: Historical Perspectives module in response to the question, 'In Mill's view, of what kind of proof is the principle of utility susceptible? Is it really capable of any kind of proof?'

This is impressive, as much for the questions it throws up as for the detail with which you go into Mill's considerations in favour of the principle of utility. For that reason, I found it rewarding to read. However, there is also an important lacuna, and a red herring.

The lacuna is easily missed because the point is made very early on in Utilitarianism. This is where Mill argues against what he terms 'intuitionism'. You would have thought that with his stress on the foundational aspect of 'what we desire' as being that which determines what is 'desirable', Mill would have given some credence to the evident fact that people do in fact have strongly held moral beliefs -- derived from religion, or their moral conscience -- which are, in effect, desires about how they and others *should* behave. Yet he is adamant that any attempt at basing ethics on such 'intuitions' is worthless. It begs the very question he is seeking to answer. If my moral intuitions differ from yours, there can be no argument or discussion, whereas the point of moral philosophy is to discover a common coin in which the questions of ethics can be rationally discussed.

This starting point leaves very little alternative to a consequentialist ethics. Although Mill ventures the hypothesis that his utilitarianism is close to what Kant intended by the categorical imperative (!) he does not make any attempt to assess the prospects for an a priori or logical basis for ethics in the manner of Kant. So I would call Mill's rejection of intuitionism, 'Step 1'.

The red herring is Mill's view about deduction. I sympathize a lot with this view. However, the way I would put Mill's point is that when we represent arguments in deductive form -- whether they be arguments in science or in philosophy, or in any other subject -- this necessarily obscures to some extent the *real* inferences involved. The point of deductive arguments in philosophy is not to arrive at new knowledge, but rather dialectical: to erect a structure which will enable a critic to see the points where a process of reasoning can be questioned or attacked. That is how Plato characterizes the 'dialectic'. That is what you have done, in representing Mill's 'proof' of the principle of utility.

I'm not saying that philosophers are never tripped up by logical fallacies. Only that what at first looks like a 'fallacy' or 'non-sequitur' is more often than not an inference for which the author has not offered sufficient inferential support.

The idea that deduction can never yield new knowledge is of course rubbish. You only have to look at mathematics, to discover a rich field of genuine discoveries which arise through following a logical argument. In 'The Justification of Deduction' Michael Dummett describes the challenge to any account of the philosophical basis of logic, of reconciling the utility of logic (yielding new knowledge) with the possibility of justifying a (given) system of logic (e.g. for Dummett, classical vs. intuitionist). But I would argue that Mill was to a large extent right about the use of logic outside the specialized arena of mathematics or set theory, or formal logic.

Coming to the proof itself, there is a much criticized point where Mill says, or appears to say something to the effect that if it is true that all men desire happiness, then a man ought to desire the happiness of all. However, you put it, it looks like a complete non-sequitur. Yet, there is a principle at work here which you express in the formula, 'Happiness is of value independently of whose happiness it is.' What Moore (in the quote from Principia Ethica) in effect argues, and what you have persuaded me that Mill believed, is that it is, strictly speaking, nonsensical to claim that my happiness is good *because it is mine*.

The question is: What should I do? The egoist replies, 'Pursue my own happiness.' Why only my happiness? 'Because it's mine.' But that's not an intelligible reason, any more than 'I am I' is an informative statement. (I would argue that this proof is only open to someone who has successfully refuted the transcendental solipsist: cf. the Pathways Moral Philosophy program, but that takes us too far off topic.)

However, this is not the only basis for Mill's claim. As you observe, Mill also says (a la Hume) that, as a matter of natural fact, the kinds of beings that we are lead us to desire happiness for others. And this is as 'foundational' as you can get.

So we have a choice: between what presents itself as an a priori proof, and the foundational empirical fact about what human beings are 'like'.

To this, you add a further consideration, which I think is incorrect as an exposition of Mill's case for utilitarianism. This is where he talks about those who are 'competent to judge' between two different pleasures. It is clear that in the context the question is not the justification for the principle of utility but rather a tweak to Mill's version of utilitarianism, which allows for higher and lower pleasures. I can see how you might think that the 'competent judge' idea could be brought in to bolster the argument for the principle of utility itself, but (to my recollection) Mill does not do this, and I don't think it is very persuasive anyway.

The point about a competent judge is that you need to know both sides. I know the pleasures of philosophy and pushpin while you only know the pleasures of pushpin, so I am the only one competent to judge that the pleasure of philosophy is greater. To make this effective as an argument for the principle of utility, one would have to say that I know the pleasure of increasing my own happiness and also the pleasure of increasing the happiness of others, while you only know the pleasure of increasing your own happiness. Therefore, I am the only one competent to judge that the pleasure of increasing the happiness of others is 'higher'.

Despite my criticisms, there is excellent work here. In an exam, you could probably obtain a mark of 70 or above.

All the best,