I wasn't talking about altruistic ethics, which can lead someone to sacrifice their lifes to prevent someone else getting a bruise;

Although it usually doesn't.

and thus would be almost as disastrous as selfishness if widespread. I was talking about cooperative ethics - which overlaps with but doesn't equal altruism, same as it overlaps but doesn't equal selfishness.

I think that you version of altruism is a straw man, and that what most people mean by altruism isn't very different from co operation.

The difference between morality and immorality, is that morality can at its most abstract possible level be cooperative, and immorality can't.

Or, as I call it, universalisability.

But it's something that leads to different expectations about the world, namely what Amanojack was asking for.

That argument doesn't have to be made at all. Morality can stand as a refutation of the claim that anticipiation of experience is of ultimate importance. And it can be made differently: if you rejig your values, you can expect to antipate different experiences -- it can be a self-fulffilling prophecy and not merely passive anticipation.

In a world populated by beings whose beliefs approach objective morality, I expect more cooperation and mutual well-being, all other things being equal. In a world whose beliefs don't approach it, i expect more war and other devastation.

There is an argument from self interest, but it is tertiary to the two arguments I mentioned above.