Is true, honest-to-god deontology possible, or is what we call deontology just far-sighted consequentialism? Kant's ends principle is the classic ethical principle from deontology, right? But even Kant's principle is inextricable (I think) from Enlightenment meliorism. That is, treating people as ends-in-themselves is moral because it leads to a better world, no? Deontology is supposed to divorce ethics from consequences, but don't attempts to establish rational moral principles still take for granted certain principles, such as human dignity, species survival, or (if nothing else) logical integrity?

This question expresses a puzzle that many philosophers have shared. However, I think that whether Kant was right or not (I think not, myself), his theory turns out not to be a form of consequentialism. This only becomes apparent when we look at the logical structure of the theory, and in particular, the difference between Kant’s views about what it is to act rationally and what consequentialism says on this matter. There are ways of making deontology and consequentialism sound very close, but I think this ends up in confusion, not reduction.

Consequentialism first. The essential structure of consequentialism is
1) a theory of what is good, e.g. happiness (or species survival, or dignity, or logical integrity) and
2) a theory of that what is right is to bring about (usually, to maximise) what is good.

It is important to the theory that how we bring about what is good is irrelevant, that we have a conception of what is good that is independent of what is right, and that we are concerned with some overall state of the world, not simply how we ourselves act. Suppose you had a form of consequentialism that says: what is good is that people do their duty (good = duty); it is always right to do your duty, irrespective of what other people do (the only consequences that matter are the immediate consequences of this one action). Then this isn’t a genuine form of consequentialism at all – it’s really a form of deontology!

Deontologists, by contrast, typically do say that we have duties regarding our own actions, rather than states of the world. I have a duty to keep my promises, but I don’t have a duty to make sure promises are kept. Deontology claims that we should each be most concerned with complying with our duties, not attempting to bring about the most good. In fact, all deontologists agree that there are times when we should not maximize the good, because doing so would be to violate a duty. So even if Kant, as a deontologist, took dignity or logical integrity as a principle, as you suggest, he would likely say that we shouldn’t sacrifice dignity in order to produce more dignity in the future or commit logical fallacies in order to produce logical integrity in others. (Philip Pettit puts this in terms of honouring v. promoting. Deontologists honour a value; consequentialists promote it.)

We can get deeper into the contrast through Kant’s idea of a good will. For the consequentialist, a good will is one that wills good ends, i.e. we are good if we aim to bring about what the theory says is good. But Kant argues that this cannot be correct, because there are no ends that are good ‘without qualification’. Anything, apart from the good will itself, can either be bad or contribute to what is bad. For instance, intelligence and self-control are good – but they can enable someone to do clever or difficult bad things, if that is what they choose. Power can be good, but it depends on what use we put it to. If someone is made happy by hurting others, their happiness is morally bad. So we evaluate happiness by morality. And so on.

What of dignity and logical integrity? It turns out that these are not ends that are independent of the good will. What logical integrity (= rationality) requires, practically speaking, and characterises human dignity, turns out to be bound up with the nature of a good will. To aim at these things is, Kant argues, to aim at having a good will. They aren’t independent ends so much as structural features of the good will. (And it is unhelpful to say that this is a form of consequentialism because the good will can be defined as aiming at the good end of being a good will!)

This challenges the very understanding of practical reasoning – reasoning about what to do – in consequentialism. Put simply, consequentialism understands all practical reasoning as means-end reasoning: it is rational to do whatever brings about a good end (and usually, the consequentialist holds that if something is good, more of it is better, and we ought to do what is better). Kant disagrees and offers an alternative theory of practical reasoning. The good will can’t be defined by means-end reasoning, because there are no ends that are good without qualification. Instead, he argues that to have a good will, I should act only on maxims that I can also will everyone to act on. This is, of course, the first formulation of the Categorical Imperative.

But what of the formula, ‘Act in such a way that you always treat humanity, whether in your own person or in the person of any other, never simply as a means, but always at the same time as an end’. I think you are right, that this formulation is really fundamental to Kant’s ethics: But I don’t think it says that treating people as ends in themselves is good, so it is right to do so – which would be the consequentialist interpretation.

To understand this, let us return to the idea of the good will. Because only the good will is good without qualification, it is the only thing of unconditional value. Everything else that is valuable depends, in some way, on the good will. For instance, intelligence is valuable for all sorts of purposes. In other words, it is valuable as a means to an end. Its value, then, depends on the value of its end. What gives its end value? We do, says Kant. Something is only an end if it is adopted by a will. It is our adopting something as an end that gives it value. Because I have desires and purposes, various things in the world are valuable to me.

So far, value is subjective. However, this does not apply to other people (or rational beings generally). Your value is not simply your value to me as a means in relation to some purpose or desire I have. It is not even your value to you (you might have very low self-esteem, and wrongly underestimate your value). We have ‘intrinsic worth’, which Kant identifies as ‘dignity’. What gives us this dignity is our rational will. The will has unconditional value as the thing which gives value to everything else. So in the second formulation above, by ‘humanity’, Kant means our ability to rationally determine which ends to adopt and pursue. To treat this ability always as an end means never to subordinate it to achieve something else. Such an action contradicts the value of any end whatsoever. It’s an incoherent thing to do. The will is bound, by its rational nature, to respect the will (of others and ourselves) as the origin of value.

Ok, so that’s the structure of the theory, as I understand it. And it’s not a consequentialist structure. So, at least until we start getting into objections and replies, honest-to-God, true deontology is possible. (That doesn’t make it right.)

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