Earlier quoted context omitted.
Unicorns exist. I have seen one. Of course, I can't prove it to you, but then, you can't prove to me that you exist.
They might as well exist, but based on my prior estimates of probabilities of different events, and Bayesian reasoning, I conclude that it's much more likely that you're insane than that you've actually seen a unicorn (I don't discard the existence of unicorns entirely, I just consider it very improbable).
And, based on those same estimates of probabilities, none of us should be here, given what we know so far.
It just strikes me as profoundly short-sighted (and unwitting self-parody) for people to claim such assuredness of the falseness of others' beliefs when we all know so very little. In truth, neither of us can prove what we know or don't know in many regards.
It matters because it also smacks of the same moral/intellectual high-ground staking that serves to dismiss entire groups of people. Sure, we can claim tolerance, but is real tolerance (i.e. seeing others as equals, respecting their beliefs vs. just allowing that they have them, etc.) truly compatible with one group believing that another is actually insane?
The approach you take is materially no different than that taken by those whom attacked Hebdo. And, you both believe your positions to be evidence-based.