[runald]

It's called circular reasoning. Conclusion cites the premises, which in turn the premises cite the conclusion. Evidence (or lack of) is used to prove it self. When you start with a false or circular premise, anything that follows is technically true. It's a powerful (bullshitting) tool that can be used to prove or disprove anything.

[mcpackieh]

It's bayesian reasoning. If I tell you that I predict the sun will explode tomorrow, you should consider the sun's track record of not exploding when evaluating my claim.

[runald]

There's no bayesian reasoning here, just someone assuming something to be proved to be already true. Statements don't become self-evidently true just because someone assigned probabilities on them.

Also, using only past billion occurrences of the sun not blowing up, and then still concluding that the sun will not blow up despite of any recent indications of the sun showing anomalous activity seems a more accurate analogy.

[emmelaich]

absence of <anything> is a better default than presence