 Is this a convincing argument? According to Buffon, we ought to ignore some small probabilities because people like him (56-year-old males) do in fact ignore them. Buffon can thus be accused of attempting to derive an “ought” from an “is”. To avoid Hume’s no-ought-from-an-is objection, Buffon would have to add a premise to the effect that people’s everyday reactions to risk are always rational. But why should we accept such a premise?