Well, I see a problem with your approach (and Greene's approach) here, which is that science doesn't give you a "should", at least not in a general sense. Scien

Well, I see a problem with your approach (and Greene's approach) here, which is that science doesn't give you a "should", at least not in a general sense. Science only helps us understand facts and processes. If you have a goal you want to achieve, science can often tell you how to achieve that goal, that is, science can tell you what you "should" do, if you have a goal. And sometimes science can help you guess what your goals might be (because people often have similar goals). This gives us some insight into these questions. We can ask, what's your goal?: > "If science tells me that I love my children more than other children only because they share my genes (Hamilton, 1964), should I feel uneasy about loving them extra?" This depends on what your goal is. Evolutionary theory tells us that most people want their offspring to survive and reproduce, and have no such goal for the survival of other people. So if that's your goal, then you should love them extra. If that's not your goal (and for some small percentage of the population it won't be) that doesn't give you any imperative, so there's no basis for saying that you should or shouldn't feel anything about your kids. > "If science tells me that I’m nice to other people only because a disposition to be nice ultimately helped my ancestors spread their genes (Trivers, 1971), should I stop being nice to people?" Again, this fact only gives you an imperative if it relates to your goals. If your goal is to spread your genes, then you should be nice to people. If that's not your goal, then Trivers' research doesn't provide any guidance as to what you should or shouldn't do. It's worth noting that there are plenty of other goals for which science might tell you that you should love your children or be nice to people. Is your goal to have someone take care of you when you're old? Then you should love your children. Is your goal to have a successful career and make lots of money? Then you should be nice to people. The most interesting part of this, to me, is that it forces us to take responsibility for our ethics. Within this framework, when you tell someone that what they are doing is wrong, you're telling them that it doesn't fit with your goals. When a society makes laws against behaviors, they're declaring that those behaviors don't fit with the shared goals of the members of the society. That doesn't mean that there is no basis for forcing one's ethics on others--often one's goals require it. For example, it is my goal to live an adequately long, healthy, and productive, so I have no qualms forcing my ethic of "do not murder" on other people. And most people share that goal, which is why murder is illegal everywhere I know of. There are a lot of different directions to explore this idea. The core, though, is simply that there's no "should" without a goal.