Contrary to its 'Age of Reason' moniker, the Enlightenment's key advance was acknowledging human fallibility. This humility challenged the absolute certainty of earlier philosophies which used pure reason to justify dogma like geocentrism. Accepting the limits of reason opened the door to empirical evidence and intellectual dissent.

Understanding economics requires hands-on experience, like running a business with personal financial risk. Purely philosophical knowledge leads to unworkable ideas because it lacks a grasp of real-world cause and effect, where a bad decision could cost you your house.

While modern Stoicism is popular, Hume found its core tenet—valuing only what's in your control and suppressing emotion—to be impossible and undesirable. Attempting this level of detachment dampens positive emotions along with the negative, rendering life inert. Adopt useful Stoic tactics without embracing the emotionless ideal.

Economic theory is built on the flawed premise of a rational, economically-motivated individual. Financial historian Russell Napier argues this ignores psychology, sociology, and politics, making financial history a better guide for investors. The theory's mathematical edifice crumbles without this core assumption.

Citing philosopher Alex O'Connor, the human brain is not optimized for raw data but for narrative. By asking people to abandon myth and story—the things that feel most real—in favor of statistics, the rationalist movement is asking people to fight their own cognitive wiring.

Work by Kahneman and Tversky shows how human psychology deviates from rational choice theory. However, the deeper issue isn't our failure to adhere to the model, but that the model itself is a terrible guide for making meaningful decisions. The goal should not be to become a better calculator.

Post-WWII, economists pursued mathematical rigor by modeling human behavior as perfectly rational (i.e., 'maximizing'). This was a convenient simplification for building models, not an accurate depiction of how people actually make decisions, which are often messy and imperfect.

While "big ideas" are powerful, Hume cautioned against the intellectual arrogance of adopting a single theory as a universal explanation. Over-relying on one framework, from social change models to diet fads, leads to error. The biggest ideas are still only small parts of a much larger, more complex reality.

We operate with two belief modes. For our immediate lives, we demand factual truth. For abstract domains like mythology or ideology, we prioritize morally uplifting or dramatically compelling narratives over facts. The Enlightenment was a push to apply the first mode to everything.