backfire
Explanation
The Joke
A woman asks a bald man with glasses whether he believes in the "backfire effect" -- the psychological phenomenon where people who are presented with evidence contradicting their beliefs actually become more entrenched in those beliefs rather than changing their minds. The man confidently explains: "Of course. People have beliefs, and when they hear contrary views they dig in their heels."
The woman then tells him that "there are several studies now that appear to disprove it." Without missing a beat, the man angrily slams the table and shouts "THEN THEY ARE LIES!" -- immediately demonstrating the very effect he just described, by refusing to accept evidence against his belief in the backfire effect.
The Humor
This is a perfectly self-referential joke. The man exhibits the exact cognitive bias he was just explaining, by having a backfire-effect reaction to being told the backfire effect may not be real. The irony is airtight: his belief in the backfire effect is itself subject to the backfire effect. It also works as a commentary on how people who consider themselves knowledgeable about cognitive biases are not necessarily immune to them -- in fact, confidence in one's understanding of psychology can itself become a form of intellectual rigidity.
References
- The "backfire effect" was popularized by a 2010 study by Brendan Nyhan and Jason Reifler, which found that correcting political misinformation sometimes strengthened people's attachment to the false belief. Subsequent research has had difficulty replicating the effect, leading to debate about how robust it actually is.