Ah, but my admittedly nonexpert understanding is that the early Buddhists were talking about "right" action only in an instrumental, functional sense. The point was always about achieving results, based on knowledge of causal mechanisms, knowledge gathered by intensive introspection. This is compatible, then, with naturalistic nihilism, which is quite different from other religions.

Buddhism is a therapy which may amount to the mere conditional statement that if you want to end your suffering, here's how you do it. The early Buddhists were sort of like Jews in eschewing theological speculations, which made Buddhism more philosophical or proto-scientific than wildly idealistic.