In an interesting piece of science, Nautilus looks at what happens to our brains when we don’t tell the truth. It turns out that the more you lie, the more truthful it seems. Because while a lie might initially appear to the brain as a lie—a fabricated memory sets off your brain’s alarm bell—over time its “source-monitoring” fatigues with each fib. Lying cements the false details at the expense of the real ones.

Psychologist Quin Chrobak said that if a lie or fabrication provides an explanation for something, it’s more likely to become confused with what’s true. He said, “People are causal monsters. We love knowing why things happen,” and if we don’t have an explanation for something, we “like to fill in the gaps.” The pressing human need to fill those gaps, might also pertain to beliefs we hold about ourselves.

Another important factor underlying this effect is repetition. Psychology professor Kerri True explained, “If I tell the lie to multiple people, I’m rehearsing the lie.” And rehearsing a lie seems to enhance it. “The more you repeat something,” Chrobak said, “the more you actively imagine it, the more detailed and vivid it becomes,” which further exploits the brain’s tendency to conflate detail with veracity.

What’s at stake here is more than a scientific explanation for the pathological liar in your life. This process is at work in every self-rationalization and self-justification we tell ourselves.

If falsehood fatigue could explain how people can fall down the rabbit hole of online echo chambers. It’s also a glowing advertisement for a daily/weekly reminder that we cannot trust ourselves. That the devices and desires of our heart—what we believe to be true about ourselves—are all plagued by faulty wiring.

Regularly confessing one’s frailty in this regard might just reset the brain’s falsehood fatigue and bring you closer to the Truth that sets you free.

Possible Preaching Angle:

While this primarily applies to a person’s personal life, it also applies to politicians and governments. Hitler and his henchmen famously said, “If you tell a big enough lie and tell it frequently enough, it will be believed.” Quoting from the book The Crown of Life (1869). Ultimately all lies can be traced to Satan for “he is a liar and the father of lies” (John 8:44).