Back in 1996, physicist Alan Sokal decided to play a practical joke. He wrote an article for Social Text, a postmodernist magazine published by a nearby university. (Nearby to him. Not to me.) He felt that postmodernist thought was insufficiently rigorous, and they would fail to notice that no part of his article was backed by any actual physics, and was one big non-sequiter. There were loads of amphiboly, half-baked references, and misleading quotes from the last hundred years of intellectuals. Surely, they would consult a physicist who would point the the infinite problems with it?
No such luck for them. They made one attempt to ask Dr. Sokal for a rewrite, and when he refused, they just published it anyway. He then announced to the world that it was just a practical joke. Social Text protested that he wasn't being fair, but the point was made: postmodernists are really really easily trolled.
His essay is still available, and I highly recommend reading it. He starts off saying things that postmodernists generally agree with, that there is no absolute truth, but truth is a matter of perspective, and claims to absolute truth are both wrong and arrogant. He then goes on to claim that science, specifically quantum physics, supports the (American) left-wing political positions, that morphic fields exist (this was a new-age idea that not even new-age believers accept anymore), and that math supports the pro-choice opinion via the axiom of choice. (The Axiom of Choice has literally nothing to do with the political position of Pro-Choice. The Axiom of Choice says that if you have sets that contain things, things can be selected from them. Duh. Pro-Choice proclaims that abortion of pregnancy should be a legal option. Please do not debate either here. The Axiom of Choice is well-proven, and abortion is so controversial in the United States that no productive debate on it can happen. The two factions literally have opposite assumptions.) He proclaims again that absolute truth is false based on the loss of Newton's beliefs in absolute space and time, since Einstein proved that both can be distorted.
Postmodernists got the last laugh in this, ultimately, as Schon and the Bogdanov brothers released physics papers with glaring errors that weren't noticed until long after publication, with the Bogdanov brothers escaping the notice that they had no qualifications either. A further lesson: Peer review only works when the peer is actually paying attention. The Bogdanov affair was particularly embarrassing because many of their claims were outright impossible, and no one noticed.
Confirmation biases also appear in Dr. Rosenhan's experiment in which he has actors pretend to be insane until admitted to a mental hospital, and then return to sanity. Doctors in these hospitals continued to find their normal behavior to be also crazy, since these people were admitted as insane. This also happened in the opposite direction as a mental hospital that heard about the experiment found suspect "patients" that were, in fact, legitimate. Dr. Rosenhan hadn't even sent actors to that hospital.
Lesson had: Check carefully, fraud is easy.