I was just telling a member of the studio audience late last week that it was time for me to write a few posts on moral theory. Coincidentally, a couple other members of the studio audience decided to give me the opening to do just that.
For example, let's say that someone wishes to lash themselves to punish themselves for a deed that they committed which they feel guilty for and to pay penance to God. If this person lived on a monastery then that action would fall under that category of a desire that people have a desire to promote, but if they were living in a secular society that would probably fall under the category of of a desire that people have a reason to inhibit.
No, it would not. It would fall under the category of a desire that people believe they have reason to promote or inhibit respectively, but this does not imply that it is a desire that they have reason to promote or inhibit in fact.
Desires are propositional attitudes that can be expressed in the form, "Agent desires that P", where P is a proposition (a sentence) capable of being true or false. A desire that P is fulfilled in any state of affairs in which P is true.
So, people can have a desire to "pay penance to God", but this is a desire that cannot be fulfilled. This is because there is no state of affairs in which the proposition, "I am paying penance to God" is true. People might come to believe that this desire is being fulfilled, but it is not a desire that anybody in fact has ever fulfilled.
There is no evidence that any person in all of human history has ever fulfilled a "desire that I am paying penance to God," by lashing themselves or by any other means. Ever.
In saying the, it is also the case that people generally have many and strong reasons to promote an aversion to violent interference in other people's mistakes. I typically refer to John Stuart Mill's On Liberty for a solid defense of that moral principle. However, the fact that we have no right to interfere violently with those people who harm only themselves does not contradict the fact that they are mistaken.
Your definition of good is entirely dependent on the moral atmosphere of the society that the person is living in and cannot say anything about good or evil objectively.
You get this by confusing what people believe will fulfill a desire (which is entirely dependent on the given culture) with what does, in fact, fulfill a desire. What people believe fulfills a desire has no more relevance to moral facts than beliefs about the age of the earth have for biological and geological facts. You take at face value the fact that people in a particular culture believe that P, and you bring it into the theory as if P were (or could be made to be) true, even though P is not and cannot be made to be true.
Now, this still leaves open the issue:
First of all it's far to vague, the phrase "malleable desires that people generally have reason to inhibit" is so vague it's borderline moral relativism.
I will deal with that tomorrow.