On ‘Ought Implies Can’ in Ethics and Epistemology

Posted on August 31, 2016 by

I recently got into a discussion about the ‘ought implies can’ (OIC) principle on social media. The poster suggested that he bought the principle in ethics but maybe not in epistemology. Disclaimer: I buy it wholeheartedly in ethics, and I’m inclined to buy it in epistemology as well. But pulling apart OIC in different realms seems to be a tenable position, after all there may very well be different requirements on believing X than there are on doing X. Fine. But then what is this difference? After all, if one is compelled to accept OIC for actions that one cannot perform, what changes regarding obliging one to believe something that one cannot believe? I initially posed the questions as they appear below:

I asked, “So you think you ought to believe things that you *cannot* believe? How can one be obligated to do something or believe something that one does not have the power to believe or do? If ability is not tied to what one is obligated to believe, then do rocks not have an obligation to believe certain things? One obvious answer is that rocks are not the sort of thing that CAN believe X. But if a person can’t but believe Y, why think they are in any better position to believe X than the rock is?”

Now, I turn to you all. If you buy OIC in ethics, does it make sense to reject it when discussing our obligations to believe?

What do you say?


For what it’s worth, Ive posted about OIC and discussed the principle in the comments here, here, and here among other places.