What you believe to be true is influenced by how much you want it to be true. The more something helps you deal with uncertainty, the lower the bar is for you to believe it’s true.

Describing the Great Plague of London, Daniel Defoe wrote in 1722: “The people were more addicted to prophecies and astrological conjurations, dreams, and old wives’ tales than ever they were before or since.” You’ll believe just about anything that offers hope when a plague is killing a quarter of your neighbors.

There’s a thing in the legal world called Gibson’s Law, which states that, “For every PhD there is an equal and opposite PhD.” No matter what argument you’re trying to make, you can find a qualified expert witness who’s willing to make it, under oath, for $500 an hour.

People can be led to believe and defend almost anything, because the goal of a belief is often not to discover what’s true – it’s to justify past actions, or protect your reputation, or provide hope when it’s lacking, or to maximize your income, or to signal to others that you belong to the tribe.

A belief’s allure can eclipse its truth.

There’s no way you can remember all the details; there are just too many. So in your recollection you emphasize some memories (sharpening) and discard others (leveling).

What you think is true is heavily based on what you’ve experienced, and you remember the parts of your experiences that make good stories, confirm stereotypes, and connect dots between other experiences.

It is far easier to fool yourself into believing a falsehood than admit a mistake. Changing your mind is rarer than it should be, leading us to cling to false beliefs.

The core of a scientific lifestyle is to change your mind when faced with information that disagrees with your views, avoiding intellectual inertia, yet many of us praise leaders who stubbornly stick to their views as “strong.” The great physicist Richard Feynman hailed “distrust of experts” as a cornerstone of science, yet herd mentality and blind faith in authority figures is widespread. Logic forms the basis of scientific reasoning, yet wishful thinking, irrational fears, and other cognitive biases often dominate decisions.

Beliefs are not just about what we know; They are social signals that offer clues about how we established our beliefs, our confidence in our intelligence, and our ability to pass reliable truth to other people.

We should want an expert who is willing to change their mind, but what we actually want is someone who’s confident enough to never have to.

A lot of times we’re not interested in truth – we’re interested in the elimination of uncertainty, and that fact alone causes us to believe things that have little relation to reality.