Gary Marcus, the psychologist who wrote that most excellent book, Kluge: The Haphazard Construction of the Human Mind, has written a nice essay that tears into that most annoying concept that some skeptics and atheists love: that without a proof, we’re incapable of dismissing certain especially vague ideas. It’s a mindset that effectively promotes foundation-free ideas — by providing an escape hatch from criticism, it allows kooks and delusional thinkers, who are not necessarily stupid at all, to shape their claims to specifically avoid that limited version of scientific inquiry.
Marcus goes after two representatives of this fuzzy-thinking concept. Schmidhuber is an acolyte of Kurzweil who argues for a “computational theology” that claims that there is no evidence against his idea, therefore the universe could be a giant software engine written by a great god-programmer. Eagleman is a neuroscientist who has gotten some press for Possibilianism, the idea that because the universe is so vast, we should acknowledge that there could be all kinds of weird possibilities out there — even god-like beings. “Could be” is not a synonym for “is”, however, and science actually demands a little more rigor.
Some people love to claim that an absence of a single definitive test against an idea means that it is perfectly reasonable to continue believing in it. Marcus will have none of that.
In particular, Eagleman, who drapes himself in science by declaring to “have devoted my life to scientific pursuit,” might think of each extant religion as an experiment. Followers of many religions have looked for direct evidence of their beliefs, but (by Eagleman’s own assessment) systematically come up dry. And, crucially, statisticians have shown decisively that a collection of failed efforts weighs more heavily than any single failed effort on its own. The same thing happened, of course, when scientists looked for phlogiston, and cold fusion, too. Nobody has proven cold fusion doesn’t exist, but most scientists would assign a low probability to it because so many attempts at replicating the original have failed. Any agnostic is free to believe that his favorite religion has not yet been completely disproven. But anyone who wishes to bring science into the argument must acknowledge that the evidence thus far is weak, especially when it is combined statistically, in the fashion of a meta-analysis. To emphasize the qualitative conclusion (X has not been absolutely proven to be false) while ignoring the collective weight of the quantitative data (i.e., that most evidence points away from X) is a fallacy, akin to holding out a belief in flying reindeer on the grounds that there could yet be sleighs that we have not yet seen.
That’s why I’m an atheist. Not just because there is no evidence for any god, but because all the available evidence points towards natural processes and undirected causes for the entirety of space and time. I wish people could get that into their heads. When we atheist-scientists go off to meetings and stand up for an hour talking about something or other, we generally aren’t reciting a religious litany and saying there’s no evidence for each assertion; rather, we go talk about cool stuff in science, how the world actually works, what the universe really looks like…and our explanations are sufficient without quoting a single Bible verse.