Yes, I was being funny. However, it did come to mind when I read that totally illogical line, after his logical presentation that preceded it.
Cultural programming. You lay out evidence that leads to an obvious deduction ... but then you conclude the opposite, because the logical outcome is psychologically unacceptable.
He can look at the evidence rationally, but following where it leads is too scary. Funny, it's not too scary for me. Maybe I've been beaten up by life more than Jonah has, for all we have in common.