General question about the possibility of objective moral truth

[robvalue]

Simon: I agree that the only definition of morality anyone should be concerned with is to do with wellbeing. The problem is in how that wellbeing is measured. Are you saying there is an objectively correct way to measure wellbeing, in the same way mass can be measured?

This also completely ignores the problem of intent and available knowledge, when assessing actions rather than just the consequences. For example, I never mean to reduce someone's wellbeing. But I do, by accident. Am I being immoral when I make such mistakes? If so, I wouldn't call this morality anymore. Also, I might mean to increase someone's wellbeing in a way consistent with the information I believe to be true, but I may be mistaken or missing information. Again, am I being immoral if the consequences don't match my intent? I would say intent is precisely what morality is about.

I believe it's a very vague term, one which means something slightly different to everyone. How can there be a "right" answer, until we agree on an explicit way to measure wellbeing? And if there is, but it's an assessment no one person actually agrees with, what use is it?