See that bird? It’s a brown-throated thrush, but in Germany it’s called a halzenfugel, and in Chinese they call it a chung ling and even if you know all those names for it, you still know nothing about the bird. You only know something about people; what they call the bird. Now that thrush sings, and teaches its young to fly, and flies so many miles away during the summer across the country, and nobody knows how it finds its way.

Test it this way: you say, “Without using the new word which you have just learned, try to rephrase what you have just learned in your own language.” Without using the word “energy,” tell me what you know now about the dog’s motion.” You cannot. So you learned nothing about science. That may be all right. You may not want to learn something about science right away. You have to learn definitions. But for the very first lesson, is that not possibly destructive? - Feynman

Modern tendency toward fact deficit, obfuscating generalities to mask a lack of understanding.

We take other men’s knowledge and opinions upon trust; which is an idle and superficial learning. We must make them our own. We are just like a man who, needing fire, went to a neighbor’s house to fetch it, and finding a very good one there, sat down to warm himself without remembering to carry any back home. What good does it do us to have our belly full of meat if it is not digested, if it is not transformed into us, if it does not nourish and support us? - Montaigne

Feynman Principle

  • Choose & learn about a concept
  • Attempt to convey it to a completely uninformed other
  • When you fail, go back and re-learn the impeding sub-concepts that you could not clearly articulate, as though to a child
  • Try again until succeed, then refactor (simplify further) or return to step one with a new concept

Musk calls this 'thinking from first principles':

I do think there is a good framework for thinking. It is physics – you know the sort of first principles reasoning. … What I mean by that is boil things down to their fundamental truths and reason up from there as opposed to reasoning by analogy.

Feynman Heuristics

Trustworthy people are quick to say 'i dont know, but i'll find out':

And my trick that I use is very easy. If you ask him intelligent questions—that is, penetrating, interested, honest, frank, direct questions on the subject, and no trick questions—then he quickly gets stuck. It is like a child asking naive questions. If you ask naive but relevant questions, then almost immediately the person doesn’t know the answer, if he is an honest man. It is important to appreciate that.


Beyesian updating:
Stuck between competing theories, start with priori probability (one derived from deductive reasoning, eg 'if there are two theories, both have 50% chance of being the more accurate). Then, add Beye's Theorem:

We modify our opinions with objective information: Initial Beliefs + Recent Objective Data = A New and Improved Belief. … each time the system is recalculated, the posterior becomes the prior of the new iteration. It was an evolving system, with each bit of new information pushed closer and closer to certitude.

We tend to either dismiss new evidence, or embrace it as though nothing else matters. Bayesians try to weigh both the old hypothesis and the new evidence in a sensible way.


As new evidence comes to light (eg new methods of experimentation), the results/outcomes should show the effect getting stronger/more concrete. If new methods produce less certain results, our way of thinking is likely inaccurate and needs weight adjusted Bayesian updating.


The plural of anecdote is not data. Defensible statistical sampling is key to overcoming bias and anomaly.