eli5: Carl Sagan’s absence of evidence

Question

Big fan of Carl Sagan, he was like a father figure to me, I’m partially molded by him.
That said, something he used to say all the time really baffled me, still does:
“Absence of evidence is not evidence of absence”
He said this when talking about aliens.
However: Sagan was a famous non believer.
How does this aphorism reconcile with the existence or non existence of a god?
If “absence of evidence is not evidence of absence” does that apply to a god as well?
Is there a god even though there is no evidence of him/her/it?

In: 95

Answer 1

I like to pair that expression with another Saganism: “extraordinary claims require extraordinary evidence.”

Just because there’s no evidence for something, it doesn’t mean that thing definitely doesn’t exist. On the other hand, if you’re going to make an extraordinary claim, you better have some pretty compelling evidence to back it up.

If your claim is that it’s statistically likely that intelligent life on other planets exists, but that it’s so far away we’ll likely never encounter it, that’s not a particularly extraordinary claim. There are 200 billion trillion stars in the universe, and a truly unfathomable number of planets. The idea that on at least one other planet somewhere out there, there is sentient life, is not a particularly extraordinary claim, so even though we don’t have any direct evidence, it makes sense to believe it’s likely.

On the other hand, the claim that there is an omniscient, omnipotent being who controls the universe and all of our lives and creates the cold and everything in it, and so on, that’s … pretty extraordinary. If you want me to believe that’s likely, you’re going to need to show me some evidence.

If you tell me your neighbour owns a golden retriever, I may not have any evidence that dog exists, but it seems fairly likely to be true, and even if I don’t have any proof, it’s reasonable to believe you.

If you tell me your neighbour owns a six-legged dog-moose hybrid with purple polka dots and wings, I’m gonna want to see some proof before I accept it as true.