Via Political Theory Daily Review, Joshua Greene looks at what neuroscience means for the ethics, in Nature Reviews:
The big meta-ethical question, then, might be posed as follows: are the moral truths to which we subscribe really full-blown truths, mind-independent facts about the nature of moral reality, or are they, like sexiness, in the mind of the beholder? One way to try to answer this question is to examine what is in the minds of the relevant beholders. Understanding how we make moral judgements might help us to determine whether our judgements are perceptions of external truths or projections of internal attitudes. More specifically, we might ask whether the appearance of moral truth can be explained in a way that does not require the reality of moral truth.
As noted above, recent evidence from neuroscience and neighbouring disciplines indicates that moral judgement is often an intuitive, emotional matter. Although many moral judgements are difficult, much moral judgement is accomplished in an intuitive, effortless way. An interesting feature of many intuitive, effortless cognitive processes is that they are accompanied by a perceptual phenomenology. For example, humans can effortlessly determine whether a given face is male or female without any knowledge of how such judgements are made. When you look at someone, you have no experience of working out whether that person is male or female. You just see that person’s maleness or femaleness. By contrast, you do not look at a star in the sky and see that it is receding. One can imagine creatures that automatically process spectroscopic redshifts, but as humans we do not. All of this makes sense from an evolutionary point of view.