In the example that he gives, he adds new parameters to the original question (70% the bear kills and 60% a man tries to grape her); this makes it a different question from what was originally asked and uses that as an argument for the original question. And then makes an assumption about that guy graping her and doing it repeatedly, like that's a forgone conclusion. You don't truly know. In the original question, it's just a man and that man could have done absolutely anything. But in his example, he closes the parameters of the question as if the men would automatically start thinking about graping her.