Robin Hanson suggests that recent changes in moral attitudes (in the last few hundred years) are better explained by changing circumstances than by progress in moral reasoning.
This seems plausible to me. It also seems likely that there would be a bit of a lag between the change in circumstance and the common acceptance of the new morality. (The sexual revolution following the introduction of the pill seems like a good example.)
Suppose this is broadly right -- that moral attitudes follow circumstances. Is there anything we can predict about where moral attitudes will be in the next few decades (or economic doublings), based on either recent technological or economic changes, or on those we can see on the horizon?