“Ought” Implies “Evidence”

This chapter argues for the principle that “ought” implies “evidence”. Since objective consequentialism is incompatible with this principle, the chapter provides another argument against objective consequentialism. According to “ought” implies “evidence”, a person is morally obligated at t₁ to φ at t₂ only if the evidence available to the person at t₁ suggests that her φ-ing at t₂ has an ought-making feature. The justification provided for “ought” implies “evidence” builds on the considerations supporting “ought” implies “can”, which were examined in the previous chapter: intuitive plausibility, the action-guidingness of moral theories, considerations of blameworthiness and fairness, and the nature of moral reasons. “Ought” implies “evidence” is contrasted with the standard view, according to which lack of evidence for the presence of morally relevant facts is not a defeater of moral obligation but an excuse. Finally, “ought” implies “evidence” is defended against two objections. The first objection states that the acceptance of “ought” implies “evidence” commits us to the implausible view that lack of normative evidence is a defeater of moral obligation. According to the second objection, the acceptance of “ought” implies “evidence” commits us to the implausible view that moral uncertainty is impossible.