Unknown, that is trivially false. “Should” cannot mean EXACTLY the same thing in those two sentences. I can reasonably translate the first one to: “If you do not open the door before attempting to walk through it, then you will fail to walk through it” or “then you will run into it at hurt yourself.” You have even identified the point of opening the door: to walk through it. What goal has the murder failed to achieve or worked against?
(It fails if you try to translate both shoulds into “it would be better if...” Recursive buck one step back, translate “better.”)
I am actually quite happy to translate all shoulds as instrumental variations on “do x or else some undesirable circumstance happens.” There may be many steps between x and the circumstance, or it may take some explanation/reflection to show that circumstance as undesirable, but given a fundamental value, we can estimate the probability that any action furthers it. “You should not x if you want y.”
But that is agreeing with poke. There is no “good” there apart from the y. Many people seem to have a vague sense of metaphysical or supernatural “good” that they would see as something quite different from poke’s “should open the door.”
Unknown, that is trivially false. “Should” cannot mean EXACTLY the same thing in those two sentences. I can reasonably translate the first one to: “If you do not open the door before attempting to walk through it, then you will fail to walk through it” or “then you will run into it at hurt yourself.” You have even identified the point of opening the door: to walk through it. What goal has the murder failed to achieve or worked against?
(It fails if you try to translate both shoulds into “it would be better if...” Recursive buck one step back, translate “better.”)
I am actually quite happy to translate all shoulds as instrumental variations on “do x or else some undesirable circumstance happens.” There may be many steps between x and the circumstance, or it may take some explanation/reflection to show that circumstance as undesirable, but given a fundamental value, we can estimate the probability that any action furthers it. “You should not x if you want y.”
But that is agreeing with poke. There is no “good” there apart from the y. Many people seem to have a vague sense of metaphysical or supernatural “good” that they would see as something quite different from poke’s “should open the door.”