I do not believe that the source of value is unitary — displaying apparent multiplicity only in its application to the world. I believe that value ha… - Thomas Nagel

I am not adverting here to the alleged privacy of experience to its possessor. The point of view in question is not one accessible only to a single individual. Rather it is a type. It is often possible to take up a point of view other than one's own, so the comprehension of such facts is not limited to one's own case. There is a sense in which phenomenological facts are perfectly objective: one person can know or say of another what the quality of the other's experience is. They are subjective, however, in the sense that even this objective ascription of experience is possible only for someone sufficiently similar to the object of ascription to be able to adopt his point of view — to understand the ascription in the first person as well as in the third, so to speak. The more different from oneself the other experiencer is, the less success one can expect with this enterprise.

Common sense doesn't have the last word in ethics or anywhere else, but it has, as J. L. Austin said about language, the first word: it should be examined before it is discarded.

That is what is meant, I think by the allegation that it is good simply to be alive, even if one is undergoing terrible experiences. The situation is roughly this: There are elements which, if added to one's experience, make life better; there are other elements which, if added to one's experience, make life worse. But what remains when these are set aside is not merely neutral: it is emphatically positive. Therefore life is worth living even when the bad elements of experience are plentiful, and the good ones too meager to outweigh the bad ones on their own. The additional positive weight is supplied by experience itself, rather than by any of its contents.