This comes courtesy of Theoretical Bullshit. It is a precis of the end of his excellent video found here:


Let’s imagine a thought experiment:


God comes to you and tells you there are transcendent, unconditional moral oughts. Just imagine that in this world all the things you ‘ought’ to do, from a moral point of view (a moral ought), happen to cause unfathomable pain, suffering and injustice and will land you up in hell where you will experience eternal torment. And just imagine that in this world, all the ‘ought nots’ happen to promote peace, health, happiness and justice and will ultimately land you in heaven where you will have eternal bliss alongside your Creator.


What course of action would you take – how would you live your life? Would you adhere to these transcendental moral oughts.


This shows that our lives are not bound by unconditional, transcendental moral oughts but by rational oughts. Our choices and our behaviour is informed by rationalisations depending on the circumstances we wish to actualise. Whether a god exists or not, a world in which transcendental moral oughts exist would be indistinguishable from a world in which only rational oughts exist. Therefore, not only can moral oughts be seen as trivial, but they also have little practical value. It does nothing to give our moral claims a more solid foundation.


Saying that we need transcendental, intangible unconditional moral obligations in order to have objective moral facts is the same as saying we need transcendental, intangible, medical obligations in order to have facts about medical health.


Morality is the science of maximising social and societal wellbeing just like medicine and nutrition are the science of maximising physiological wellbeing. Moral facts, just like medical facts, exist. There are empirically moral and empirically immoral things that we can do.


If your moral philosophy is completely divorced from real world issues of happiness and suffering, if morality has nothing to do with the pursuit of maximising wellbeing. If it truly has no stake whatsoever in actualising an ideal circumstance in this life or the next….


then what bloody use is it?