Religion
In reply to the discussion: Dartmouth physicist, known for doubting skeptics, wins 2019 Templeton Prize [View all]Major Nikon
(36,900 posts)All theistic religions in which I'm aware base their entire theology on the certainty that one or more deities do in fact exist. So even if it were true that atheists must believe in non-existence of deities (and it isn't), then impeaching this position must also impeach the theists' unprovable position. Then if one uses reason to analyze the dichotomy you find that one of those two claims is quite extraordinary while the other isn't at all.
The argument Gleiser and you are making is actually a false dichotomy and is fallacious. Atheism doesn't require belief of non-existence of deities, only the rejection of belief in deities. Most atheists are apatheists.
Even if one buys into the false dichotomy Gleiser is trying to establish, his reasoning is quite foolish. Unprovable assumptions are used quite frequently in the realm of science and without them our understanding of the universe would be extremely limited.