The availability of alternatives, as well as the circumstances and costs surrounding each alternitive, will influence our scale of values at the moment.

To be sure, most of us will value our own lives very highly most of the time.

But suppose that a man or woman has been seriously injured and is suffering great pain. He or she knows that they will not recover, and might linger for months or years on a bed of pain. He or she might, with entirely sound reasoning, prefer death to life under those circumstances when he cannot otherwise avoid them.

Every human being has many desires. He or she spends his or her entire life trying to satisfy their wants, one way or another.

The different objects that each believes that he or she wants are certainly not matters of instinct. Similarly, the different desires he or she has may or may not be instinctive.

The fact that he or she desires at all, however, is probably an instinct, and therefore entirely unavoidable.