So first of all, that's not what Sam Harris means so stop invoking him.

I'm not sure what you're referring to here, but here's my comment explaining how this relates to Sam Harris.

If you are referring to facts about your brain/mind then your account is subjectivist. Nothing about subjectivism says we can't investigate people's moral beliefs scientifically.

I addressed this previously, explaining that I am using 'objective' and 'subjective' in the common sense way of 'mind-independent' or 'mind-dependent' and explained in what specific way I'm doing that (that is, the proper basis of terminal values, and thus the rational basis for moral judgments, are hard-wired facts of reality that exist prior to, and independent of, the rest of our knowledge and cognition - and that the proper basis of terminal values is not something that is invented later, as a product of, and dependent on, later acquired/invented knowledge and chains of cognition). You just went on insisting that I'm using the terminology wrong purely as a matter of the meaning in technical philosophy.

This discussion is getting rather frustrating because I don't think your beliefs are actually wrong. You're just a) refusing to use or learn standard terminology that can be quickly picked up by glancing at the Stanford Encyclopedia of Philosophy and b) thinking that whether or not we can learn about evolved or programmed utility function-like things is a question related to the whether or not moral realism is true. I'm a very typical moral anti-realist but I still think humans have lots of values in common, that there are scientific ways to learn about those values, and that this is a worthy pursuit.

You do not have to demand, as you've been doing throughout this thread, that I only use words to refer to things that you want them to mean, when I am explicitly disclaiming any intimacy with the terms as they are used in technical philosophy and making a real effort to taboo my words in order to explain what I actually mean. Read the article on Better Disagreement and try to respond to what I'm actually saying instead of trying to argue over definitions.

Now it is the case that if you define morality as "whatever that thing in my brain that tells me what is right and wrong says" there is in some sense an "is from which you can get an ought".

Ok, great. That's kind of what I mean, but it's more complicated than that. What I'm referring to here are actual terminal values written down in reality, which is different from 1) our knowledge of what we think our terminal values are, and 2) our instrumental values, rationally derived from (1), and 3) our faculty for moral intuition, which is not necessarily related to any of the above.

To answer your previous question,

Second of all, give an example of what kind of facts you would refer to in order to decide whether or not murder is immoral.

One must, 1) scientifically investigate the nature of their terminal values, 2) rationally derive their instrumental values as a relation between (1) and the context of their current situation, and 3) Either arrive at a general principle or to an answer to the specific instance of murder in question based on (1) and (2), and act accordingly.

But this is not at all what Hume is talking about. Hume is talking about argument and justification. His point is that an argument with only descriptive premises can't take you to a normative conclusion. But note that your "is" potentially differs from individual to individual. I suppose you could use it to justify your own moral beliefs to your self but that does not moral realism make. What you can't do is use it to convince anyone else.

I don't understand why people insist on equating 'objective morality' with something magically universal. We do not have a faculty of divination with which to perceive the Form of the Good existing out there in another dimension. If that's what Hume is arguing against, then his argument is against a straw man as far as I'm concerned. Just because I'm pointing out an idea for an objective morality that differs from individual to individual doesn't make it any less 'objective' or 'real' - unless you're using those terms specifically to mean to some stupid, mystical 'universal morality' - instead of the terms just meaning objective and real in common sense. Trying to find a morality that is universal among all people or all mind designs is impossible (unless you're just looking at stuff like this which could be useful), and if that's what you're doing, or that's what you're taking up a position against, then either you're working on the wrong problem, or you're arguing against a stupid straw man position.

What you can't do is use it to convince anyone else.

For the particular idea I've been putting forward here, people's terminal values relate to one other through the following kinds of ways:

1) Between normal humans there is a lot in common 2) You could theoretically reach into their brain and mess with the hardware in which their terminal values are encoded 3) You can still convince and trade based on instrumental values, of course 4) Humans seem to have terminal values which actually refer to other people, whether it's simply finding value in the perception of another human's face, various kinds of bonding, pleasurable feelings following acts of altruism, etc.