A former coworker of mine was heavily into conspiracy theories. He collected them. He didn't necessarily believe in all of them. (It would be impossible to believe in all of them because some of them contradicted each other.)

If you presented him with a strong argument why one of his theories or bits of "evidence" was bogus, that didn't bother him in the slightest. He would just move on to the next one.

His thinking seemed to be: there are so many theories, they can't all be wrong.

"There has to be a pony in here somewhere!"