 Anscombe argued that Hume’s answer cannot be right. First, is it really true that we infer that Caesar was killed on the Ides of March from the thought there were many observant people in the Senate that day? No. If anything, it’s the other way around: given that we think that Caesar was killed then and there, we infer that there must have been eyewitnesses to his death. It is not that we first establish the presence of these people, and only then infer what caused them to say what they said.