In this video Richard Feynman explains why trains don’t need differential gears
Tag: Richard Feynman
A simple explanation of how differential gears work and why they are necessary.
“The world is much more interesting than any one discipline.”
— Edward Tufte
NPR’s Science Friday talks with data scientist Edward Tufte on everything from Steve Jobs’ considerations of cognitive load to Picaso’s art.
Tufte also offered some insights into human nature.
If you’re told what to look for, you can’t see anything else. …
I think there’s a lot of premature labeling. Now, the situation in teaching is different. You’re trying to point out where people should see. But analytical seeing, I believe you should try to stay in the sheer optical experience as long as possible.
Once you have an idea, or somebody tells you something to look for, that’s about all you can see. I had this experience recently: A dear friend of ours has been diagnosed with Alzheimer’s, and I hadn’t seen her for about six months. And when she came and visited, I couldn’t see her anymore. I was always looking now for symptoms, how the dementia was manifesting itself. And I know about how words control scenes. I couldn’t see her through any other lens but the possible symptoms. And that one word, that one piece of knowledge, and I was self-aware of it, totally corrupted every time I looked at her.
|Still curious? Tufte’s Envisioning Information, written in 1990, still remains a must-read. Learn more about Tufte’s Feynman diagrams.|
In this clip from a documentary film shot in Yorkshire in 1973, physicist and philosopher Richard Feynman (1918-1988) talks with Fred Hoyle, an accomplished astronomer from the United Kingdom.
Feynman poses the question: “What, today, do we not consider part of physics, which may ultimately be part of physics?”
His answer (which should be cued up here at the 7:10 mark) is the initial conditions of the universe, as well as the possibility that the physical laws themselves, evolve with time.
As he explains, there was a time when we considered the properties of substances to be chemistry, but as the quantum mechanical understanding of the atom evolved, we came to discover that this was actually all a part of physics.
In physics, our acceptance of the way things are (i.e. given conditions) without wondering why they’re like that is akin to playing chess without asking where the pieces should be placed before the game even starts.
It’s as though we’re doing a chess game and we’re working on the rules but we’re not worrying about how the pieces are supposed to be set up on the board in the first place. We tell ourselves, that’s not our business, that’s the business of cosmology and how the universe came to be. It’s interesting that in many other sciences, there’s a historical question. Like geology, we ask “How did the earth evolve into its present condition?” In biology, it’s “How did the various species evolve to get to be the way they are?” But the one field that has not admitted any evolutionary question is physics. “Here are the laws!” we say. We don’t even think about how they got that way. We think, well it’s been that way forever, it’s always been that way. It’s always been the same laws. And we try to explain the universe that way. So it might turn out that they’re not the same all the time, and that there is a historical, evolutionary question.
This fascinating conversation between two great minds continues in the follow-up video. Listen on to hear Feynman explain why he’s afraid to speculate about things.
“He (Richard Feynman) was always searching for patterns, for connections, for a new way of looking at something, but I suspect his motivation was not so much to understand the world as it was to find new ideas to explain. The act of discovery was not complete for him until he had taught it to someone else.”— Daniel Hillis
- Simplify the problem down to an “essential puzzle.” Here’s how Danny Hillis explained Feynman’s use of simplicity: “He always started by asking very basic questions like, ‘What is the simplest example?’ or ‘How can you tell if the answer is right?’ He asked questions until he reduced the problem to some essential puzzle that he thought he would be able to solve. Then he would set to work.”
- Continually master new techniques and then apply them to your library of unsolved puzzles to see if they help. As mathematician Gian Carlo-Rota explained when describing Feynman’s use of this strategy: “Every once in a while there will be a hit, and people will say: ‘How did he do it? He must be a genius!’”
There are four steps to the Feynman Technique:
- Choose a Concept
- Teach it to a Toddler
- Identify Gaps and Go Back to The Source Material
- Review and Simplify (optional)
If you’re not learning you’re standing still. But how do we get feedback on what we’re learning? And how do we go about learning new subjects and identifying gaps in our existing knowledge?
Two Types of Knowledge
The famous Nobel winning physicist Richard Feynman understood the difference between knowing something and knowing the name of something and it’s one of the most important reasons for his success. Most of us focus on the wrong type of knowledge. The first type of knowledge focuses on knowing the name of something — what it’s called. The second, focuses on actually knowing something — that is understanding something.
Feynman created a formula for learning that virtually ensured he understood something better than everyone else. It’s called the Feynman Technique and it can help you learn anything with greater understanding. Best of all, it’s incredibly easy to implement.
“The person who says he knows what he thinks but cannot express it usually does not know what he thinks.”
— Mortimer Adler
The Feynman Technique
Step 1: Teach it to a child
Take out a blank sheet of paper. At the top write the subject you want to learn. Now write out everything you know about the subject you want to understand as if you were teaching it to a child. Not your smart adult friend, but rather an 12-year-old who has just enough vocabulary and attention span to understand basic concepts and relationships.
It turns out that one of the ways we trick ourselves is that we use complicated vocabulary and jargon and it masks our lack of understanding.
When you write out an idea from start to finish in simple language that a child can understand, you force yourself to understand the concept at a deeper level and simplify relationships and connections between ideas.
Some of this will be easy. These are the places where you have a clear undrestanding of the subject. At other points, you will struggle. These are the points where you have some gaps in your understanding.
Step 2: Review
Only when you encounter gaps in your knowledge—where you’re forgetting something important, are not able to explain it, or simply have trouble thinking of how variables interact—can you really start learning.
Now that you know where you got stuck, go back to the source material and re-learn it until you can explain it in basic terms. Only when you can explain your understanding without jargon and in simple terms can you demonstrate your understanding. This is the work required to learn and skipping it leads to the illusion of knowledge.
Identifying the boundaries of your understanding also limits the mistakes you’re liable to make and increases your chance of success when applying knowledge.
Step 3: Organize and Simplify
Now you have a set of hand-crafted notes. Review them to make sure you didn’t mistakenly borrow any of the jargon from the source material. Organize them into a simple narrative that you can tell. Read it out loud. If the explanation isn’t simple or sounds confusing that’s a good indication that your understanding in that area still needs some work.
If you follow this approach over and over you will end up with a bider full of pages on different subjects. If you take some time twice a year to go through this binder and update your knowledge you will keep your knowledge.
Step 4 (Optional): Transmit
If you really want to be sure of your understanding, run it past someone (ideally who knows little of the subject –or find that 8-year-old!). The ultimate test of your knowledge is your capacity to convey it to another.
Not only is the Feynman Technique a wonderful recipe for learning, but it’s also a window into a different way of thinking that allows you to tear ideas apart and reconstruct them from the ground up.
When you’re having a conversation with someone and they start using words or relationships that you don’t understand, ask them to explain it to you like you’re 12. Not only will you supercharge your own learning, you’ll supercharge theirs. Importantly, approaching problems in this way allows you to understand when others don’t know what they are talking about. (See Batesian Mimicry)
Feynman’s approach intuitively believes that intelligence is a process of growth, which dovetails nicely with the work of Carol Dweck, who beautifully describes the difference between a fixed and growth mindset.