If you can use Bayes Theorem to see what the evidence does to the probability of a hypothesis, can you also use BT to see what happens to the hypothesis upon the absence of evidence?
Or, if you can use P(H | E) = P(E | H)P(H) / P(E)
Can you formulate it as P(H | ~E) = P(~E | H) P(H) / P(~E) for absence of evidence?
Indeed. To put it another way, "absence of evidence" is just a different kind of evidence. If hearing a dog bark would tell you something then not hearing it bark also tells you something.
This is a thread where people can ask questions that they would ordinarily feel embarrassed for not knowing the answer to. The previous "stupid" questions thread went to over 800 comments in two and a half weeks, so I think it's time for a new one.