I do not think this question can be answered adequately unless the thinker takes a ‘moral realist’ (moral reality) position – defined as a reality independent of the Mind.
A Thought is an “immaterial activity” in an immaterial reality.
If so, how does a thought (in an immaterial reality independent of Mind) inform the Brain (a material medium dependent on Mind).
But there is, as you probably have guessed, a deeper problem involved:
The Body-Mind Problem – or, more accurately in my view, The Body-Mind-Soul Problem
So, in addition to taking a moral realist position, the thinker must also take a position regarding either the Dualism of Body and Mind, or the Dualism of Body and Soul.
But whatever position is taken – Body/Mind or Body/Soul – my question remains : How does an immaterial activity (eg thinking a thought) inform a material medium (eg the brain).
Common-sense suggests a thought (eg of lifting the arm) informs the brain (the arm lifts). But how does it do this?
The question is based on a flawed premise, namely that thinking is an immaterial activity.
In fact, thinking is a product of electrochemical activity in the brain that requires energy. In fact brain activity consumes 20% of the calories burned by the body. http://www.pnas.org/content/99/16/10237.full
This SciAm article quotes the same figure:
It is well established that the brain uses more energy than any other
human organ, accounting for up to 20 percent of the body’s total haul.
It is a fact of biology that all brain activity is a physical process taking place in the material universe, requiring energy. Cheeseburger in, philosophy out.
Therefore the premise of the question is simply incorrect as a matter of science.
ps — I see that you commented above that you call thought “immaterial” because you can’t see it. But if you cut a person open you can’t see the conversion of glucose into energy or any other biochemical process. Physical entities include processes as well as solid things. You can see a rock but you can’t see the strong nuclear force holding it together. That doesn’t make physical processes immaterial. Perhaps you are asking how the laws of physics manage to make rocks. That’s actually a pretty good question.