Published online by Cambridge University Press: 26 January 2009
Vagueness in the phrase ‘can know’ aside, the principle of (Access) An act is obligatory only if its agent can know that it is obligatory is an important principle, worthy of serious scrutiny. Its truth or falsity bears on the question of whether moral rightness, obligatoriness, etc., are a matter of factors ‘internal’ to an agent (such as motives and beliefs), or whether ‘external’ factors (such as consequences) are relevant to determining the moral normative status of acts. Moreover, Access enjoys considerable intuitive support. If I destroy Greensboro in Professor Sorensen's example by pushing the wrong button, I seem to have a good excuse to give to anyone who would accuse me of wrongdoing: ‘I had no way of knowing that this action would be wrong!’ But if I have a good excuse, then pushing the button does not seem wrong; and if that action is not wrong, then I had no obligation to refrain from pushing that button.
1 Perhaps ‘could have known’ should be replaced with ‘could have had good reason to believe’; perhaps ‘could have known’ should be understood as meaning ‘could have known at some time’ (see the final paragraph); perhaps ‘could have known’ should be replaced by ‘is not culpably ignorant that’; I leave (some of) these matters undecided.
2 Actually, the fact that God exists would not itself be a background fact, if the Divine Command Theory were true. Rather, certain facts that entail that God exists would be background facts – facts such as the fact that God has commanded such and such an action.
3 As Fred Feldman pointed out to me, it would be a mistake to suppose that in every case, I could know of the existence of an obligation only by knowing the relevant background facts. I could know inductively that acts of a certain type are obligatory, without knowing what facts, e.g., utilities, grounded those obligations. Or I could be told by a moral authority I knew to be reliable that a certain act is obligatory. But in some cases I would need to be able to know the background facts. In a case like Sorensen's button pushing example, there is no other source for the knowledge that pushing the correct button is obligatory.
4 I thank Walter Sinnott-Armstrong for a helpful discussion of these matters.
5 Thanks are due to David Braun, Fred Feldman, Rich Feldman, Walter Sinnott-Armstrong, and Roy Sorensen for their helpful comments.