I said I would follow up on Thomas Nagel's views. The first twenty minutes or so* of the video inserted below is a talk in which Nagel summarizes and critiques his friend Ronald Dworkin's view of morality. Nagel speaks (as he writes) with great clarity and seriousness. (I realize that many will find the content a bit dry, but there is interest also in the style of delivery, in the very manner of the man. Ivy League and very 20th century!)
Dworkin wants ethics to be objective, and has a clever argument which appears to demonstrate that moral claims can indeed be seen as objectively true or false even within the context of a naturalistic world view.
Nagel – correctly in my view – sees our current naturalistic world view (he refers specifically to evolutionary theory) as being "difficult to square with" the objectivity of moral claims. But, as he is not willing – for moral reasons, apparently – to give up on the objectivity of right and wrong, he rejects the current naturalistic world view.
This last move is a grievous mistake, in my opinion. He is saying, in effect, that it would be just too awful if right and wrong did not have an objective basis – and so they do have an objective basis, and the scientists must have got things seriously wrong.
I respect Nagel's honesty and directness. He goes with his moral intuitions, but I would say that they take him out of the secular mainstream.
Nagel's move in this talk, by the way, needs to be seen in the context of his long-standing insistence that science, which aspires to an objective 'view from nowhere', is incomplete for it cannot encompass or explain the reality and the realities of the first-person point of view.
This idea is associated with (because it can be used to justify) what I see as the main problem with Nagel's thinking: that he lacks, and shows little interest in, scientific knowledge.
This may not matter for certain kinds of intellectual enquiry, but scientific issues (especially relating to evolutionary biology and physics) are crucial to many of the questions Nagel addresses.
In fact, his obvious (and self-confessed) lack of knowledge in these areas makes it difficult to take his reflections on human psychology or human evolutionary or cosmic history (most recently expressed in his book Mind and Cosmos) seriously.
I don't want to posit a simplistic contrast between scientifically-trained thinkers and those with little or no scientific training, however, and suggest that only the former are worth listening to. The scientifically trained can be just as stupid and irrational as anyone else.
But it does seem reasonable to expect anyone dealing in a serious way with questions pertaining to a particular area of science to have a thorough grounding in that area, or at least in a related area of science.
* The most interesting bit, in my opinion, starts at the 14:20 mark.