In his 1997 book, The Last Word, Thomas Nagel attempted to put a succinct case for the objectivist view of morality and value. This summarises, and attempts to reinforce, the position he had been developing since The Possibility of Altruism - back in the 1960s. Early on in the discussion, he concedes that "There is no moral analogue of the external world—a universe of moral facts that impinge on us causally."[i] But he wants to be able to support the claim that "while 'passions' are the source of some reasons, other passions or desires are themselves motivated and/or justified by reaaons that do not depend on still more basic desires."[ii] He wants to find objective support for moral claims (and not just in the sense that they are objectively the claims of such and such a moral system).
The core of his argument is as follows. First, there is a generality about practical judgments, in the sense that, if A has a reason to do something in circumstances C, then B has a reason to do the same thing in precisely the same salient (internal and external) circumstances. It does, indeed, seem to me that this is follows from any plausible account of what it is to have a reason. It would even follow from a Humean account (in which reasons are based on desires) that Nagel would reject: if A has the same desires, means, and beliefs as B, then A and B seem to have the same reasons to undertake the same actions.
Second, we have to choose whether or not to "transfer" to an impersonal standpoint the values that concern us from the personal standpoint. I.e. we might have a system of values from our own perspective, while recognising that everyone else does, too, in which case all of our reasons derive from our individual interests, desires, and atachments (call this an agent-relative perspective) . Alternatively, we might each assign our own life and everyone else's an impersonal, objective value (an agent-neutral perspective).
Thirdly, the agent-relative perspective amounts to, or entails, the claim that we are objectively worthless, and that in a sense it doesn’t matter what happens to us ... except to ourselves (and, I add, whoever is actually motivated to care about us; this is a point that Nagel glosses over, but which probably does not affect his argument's logic, as opposed to its rhetoric). However, fourth, such a judgment is (according to Nagel) highly unreasonable and implausible.
The conclusion, therefore, is that persons and their interests have some kind of objective worth. It then becomes a matter of building an ethical system that best gives expression to this (supposed) insight.[iv]
It looks like all this could be packaged as a formally valid argument, although I've been finding that it's not a trivial task. Still, the idea is clear enough. If I get out of the way of a truck because I want to save my life, someone like me will do the same thing in the same circumstances. If I justify my action by saying that my life is objectively valuable, it will be very difficult for me to deny that the other person's life is also objectively valuable. If I recognise that, then I have an objective foundation for an ethical system. Recognising that other people's lives are objectively valuable - not just valuable to them - I then have a good reason not only to understand why they get out of the way of trucks, but also to help them do so, to refrain from driving trucks at them ... and so on.
There's an obvious problem here, though: normally, if I see a truck coming at me, I simply react out of fear. I don't stop to wonder whether my life is of some kind of objective worth. Our evolutionary ancestors, when confronted with the equivalent of a truck (perhaps a charging Brontotherium) doubtless reacted similarly. In situations such as this, creatures like us don't rely on deliberation about objective worth; we just scamper for cover. To adapt a memorable phrase from Bernard Williams, thinking about whether my life is of sufficient objective worth to merit saving is one thought too many. It's true, no doubt, that moral systems typically enjoin us to treat other people as having some sort of worth that is to be respected, but we are talking here about whether anything like that already exists outside of moral systems and somehow provides a foundation for them. We are talking about objective worth in a very strong, pre-moral sense. (I can think of all sorts of reasons why a workable moral system might tell us to treat each other as if we all had some inherent value to be preserved, but that is entirely beside the point.)
To get the argument to work, Nagel has to support a claim to this effect: It is not true that I and my interests are objectively of no value. To derive the conclusion he wants, he has to feed this in as a premise, but it needs some support of its own because it is exactly the sort of thing that his opponents (like me, for example) are likely to deny.
So, how does he support the claim? Simply by saying how unreasonable the claim being negated sounds, and appealing to our intuitions. But clearly that won't work. Speaking from inside a moral system into which he has been socialised, Nagel may well feel uncomfortable with the thought that human lives are of no objective moral value, but this debate is not about what sort of value or "worth" is somehow assigned to us by a moral system that we already accept. We are trying to see whether our value is somehow built into objective reality, logically prior to moral systems, and giving them support. Once we get as far as making that impoprtant distinction, there seems to be no reason at all to think that any of us have that kind of objective value or worth. Indeed, it is difficult to give the idea any coherent meaning.
Far from seeming unreasonable, the claim that Nagel wants to deny appears to be self-evidently true.
Even if an omnipotent deity placed a value on my life, it would not help Nagel's argument. To help Nagel along, we would have to be able to show that this divine being would actually be making an error - and not just proving less than all-benevolent or something like that - if it failed to do so. That, in turn, would require showing that my life has some metaphysically-grounded value, independently of whether or not the deity actually valued it! Invoking supernatural beings does not advance things at all, not that the atheistic Nagel makes any attempt to do so.
The fact is that we do not normally even think about the question of whether our lives have objective value, or worth, in the strong sense under discussion. We may sometimes speak about people having "moral worth", if we have internalised a moral system that uses such terminology, but once we step outside of all moral systems and ask what this "worth" really amounts to, then it is dificult to see that it refers to anything that actually exists independently of our invention.
None of this is to deny that we can find some sort of basis for morality, but it will have to use the contingent facts of our nature (including our social nature) and our experience. It may be a far less solid basis than Nagel would like, and what it actually supports in the way of a normative system might be more pluralistic, contradictory, and ramshackle than we ordinarily expect morality to be. I welcome this, because it seems like an intellectual strength if we can account for morality's complications and discontents, as well as its existence. It may mean that some of the ways people tend to think about morality - as something objective, consistent, and absolute - are wrong, but so be it. Indeed, that explains a great deal; it's another welcome result.
[i] Thomas Nagel, The Last Word (New York: Oxford University Press, 1997): 101.
[ii] Nagel, The Last Word: 102.
[iii] Nagel, The Last Word: 106-122.
[iv] Nagel, The Last Word: 121-22.