Everyone is entitled to commit murder in the imagination once in a while, not to mention lesser infractions. - Thomas Nagel

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.

If we tried to rely entirely on reason, and pressed it hard, our lives and beliefs would collapse — a form of madness that may actually occur if the inertial force of taking the world and life for granted is somehow lost. If we lose our grip on that, reason will not give it back to us.

[With regard to] the rather common general distinction between good and bad sex …, bad sex is generally better than none at all. This should not be controversial: it seems to hold for other important matters, like food, music, literature, and society. In the end, one must choose from among the available alternatives, whether their availability depends on the environment or on one's own constitution. And the alternatives have to be fairly grim before it becomes rational to opt for nothing.