“The X-Files,” the alien-invasion conspiracy thriller, had one of TV’s most memorable taglines: “The Truth Is Out There.” It was both a promise and a tease. Read one way, it’s a slogan of hope: The truth has been hidden from you, but you will find it. Read another way, it’s a taunt: The truth is always out there, a mirage, coming tantalizingly close but then slipping through your fingers, goading you to press further. This dynamic was, of course, a boon for a TV series that unfolded at length, over hundreds of episodes, movies and revivals. It is also part of the lure of conspiracist thinking in general. The promise of elusive answers implores you to plunge deeper, deeper, into a thriller of your own, one that you both consume and help construct. It says that the absence of answers is itself a kind of evidence. Proof is proof and so is the lack of proof. All you need to do is follow one more lead, click one more link, chasing your goal like an exotic bird, following its call of truth, truth, truth.