Questions about values—about meaning, morality, and life's larger purpose—are really questions about the well-being of conscious creatures. Values, therefore, translate into facts that can be scientifically understood.Things that make us better off are good, while things that make us worse off are bad. Simple enough.
Or is it? Does war, for example, make us better off or worse? War leads to great suffering and it corrupts our souls toward violence -- as Bernard of Clairvaux put it, it leads to mortal sin for the victor and death for the vanquished -- so it would seem to be bad. Yet millions of men have found war to be the greatest and most powerful thing in life, something to be celebrated in song rather than shunned. Many human societies have been shaped around war and military values, and it was woven all through their lives and their art. The society of the European aristocracy, which gave us all the glories of Renaissance and Baroque art, would have made no sense without their ethic of soldiery and honor.
Is it good or bad for people to suffer rejection and failure? It seems to break some people, but drive others on toward great accomplishment. Wealth and safety would probably figure on any list of good things for humans to have, and yet for many they seem to lead only to boredom, depression, nihilism, thrill-seeking, and libertarianism.
Since I am myself an existentialist who thinks that we have to make our own way in the world without divine help, my morality must at some level be the one advocated by Harris, Jeremy Bentham, and so on: what is good is what makes for human flourishing. My problem is with the second half of Harris' title, his notion that science can "determine" what is best for us. My own approach to life is rooted in my sense of how little we understand ourselves and our world. I do not think we can predict what will happen to us if we ever build a world of universal peace and wealth. It may turn out to be as awful as anti-utopian writers imagine. After all, we evolved to struggle, and without it many of us feel mainly a lack or a hole where struggle and suffering should be.
So while in practical terms I want the world to move toward peace and prosperity, there is a part of me that is glad we will not achieve them in my lifetime. I fear what that would be like for us.