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The Scientific Method: The Best Introduction

“If it disagrees with experiment, it’s wrong.
In that simple statement is the key to science.”
— Richard Feynman


The scientific method refers to a process of thought based on integrating previous knowledge, observing, measuring, and logical reasoning.

In this short video taken from his lectures, Physicist Richard Feynman, offers perhaps one of the greatest definitions of science and the scientific method that I’ve ever heard. And he does it in about a minute.

Now I’m going to discuss how we would look for a new law. In general, we look for a new law by the following process. First, we guess it (audience laughter), no, don’t laugh, that’s the truth. Then we compute the consequences of the guess, to see what, if this is right, if this law we guess is right, to see what it would imply and then we compare the computation results to nature or we say compare to experiment or experience, compare it directly with observations to see if it works.

If it disagrees with experiment, it’s wrong. In that simple statement is the key to science. It doesn’t make any difference how beautiful your guess is, it doesn’t matter how smart you are who made the guess, or what his name is … If it disagrees with experiment, it’s wrong. That’s all there is to it.

For more color watch the longer version below, which offers the next 9 minutes of the lecture. In this clip Feynman explains that guessing is not unscientific: “It is not unscientific to take a guess, although many people who are not in science believe that it is.”

The Scientific Method is part of the Farnam Street Latticework of Mental Models.