Bomb#20 doesnt discuss which moral is right. He clearifyhow science works, what an objective law is.This is where you go off the rails, at the very beginning. You're completely wrong. Enforceability is no part of the criteria for objectivity. To claim that it is is just a dressed-up way to say "Might makes right." Might does not make right. Right makes right.One of the criteria for the objective quality of an extant moral law would be its enforceability.
So, what makes right?
What is moral in one culture can appear to be horrendous in another. In the episode where Jesus tells the adulteress to "Go and sin no more," it is she who has behaved immorally and the people who want to stone her to death, who are acting morally. This seems rather extreme to us, but this peculiar bit of moral code is intended to protect one's property from theft. This woman is a man's property, and another man has diminished its value. Of course, killing her does reduce her value to zero, but there is always social value in deterrence. Which is to say, might(in this case, a crowd carrying stones) does make right.
There is no human act which can be perfectly moral, given the proper circumstances, and abhorrently immoral in other circumstances. To try to write an absolute code of right and wrong is an exercise in futility.
The law of gravity is an objective law. There is no might needed to uphold it. Its a description of how the universe works.
That what makes talk about objective moral so paradoxual. Supose someone really found an objective moral law. Then what could force us to believe it is morally right? I can only think of one way: that we were somehow hardwire to think it is morally right. But then, if we are hardwired to gave this moral then we will follow it anyway, wouldnt we? its treally not an issue, is?