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If you can’t explain something in simple terms, you don’t understand it

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Re: If you can’t explain something in simple terms, you don’t understand it

#61

Feynman also said: "Hell, if I could explain it to the average person, it wouldn't have been worth the Nobel prize." [1] Showing a limitation of the maxim or Feynman's hubris? [1] https://en.wikiquote.org/wiki/Richard_Feynman

In one of his books he told this story as follows, a cab driver watched him on TV and said to him "I cant believe you actually tried to explain what did you found." Then Feynman said "Well, what would you say?" Cab driver "If i could explain it in 2 min. then it would not be worthy." Afterwards Feynman used that line. I might be wrong though, but pretty sure he told a story like this.

Re: If you can’t explain something in simple terms, you don’t understand it

#62
post #11
post #6

In job interviews I always zone in on the most complicated thing someone has worked on and then ask them to explain it to me. Often a thesis or a project or a large system or something low level to do with OS features etc... It is amazing how rarely people can get it across to me in basic terms. In fact even the idea of breaking it down into non technical concepts seems to be surprising and alien to many people. I re…

I fail all interviews when I explain complex things in simple terms. Must be some correlation here.

It's only one way to approach things. Many good people are not great explainers. However, I do find a willingness to try and get down to first principles a good sign. I only take it badly when people seem unable to think outside their expertise, or seem unaware of the layers above and beneath the particular strata they work within.

Re: If you can’t explain something in simple terms, you don’t understand it

#63
post #29

The problem I find with this outlook is that it takes technical terms being jargon at face value. If you can't fall back on progress in language which allows you to express more complex ideas, you're not going to reach the same depth of understanding in simpler words without it taking a lot longer anyways - with most of your time spent reestablishing what you just threw out the window. If you rehash it in smaller wor…

"Education is a series of small lies." Spoken by my intro to computer engineering professor, upon telling us that most real processors actually have some ternary logic. The notion here is that educating beginners about a subject is different from communication between experts. Yes, experts use jargon because it is more efficient. But, the notion here is that if you truly understand something, you should be able to fi…

> most real processors actually have some ternary logic

Was he referring to the Z state? If so, it's not really ternary logic but rather a "no result" state for cases where there is a control signal involved (e.g., in a tri-state buffer).

Re: If you can’t explain something in simple terms, you don’t understand it

#64
post #10

Or to quote PG's Write Like You Talk [0]: And in my experience, the harder the subject, the more informally experts speak. Partly, I think, because they have less to prove, and partly because the harder the ideas you're talking about, the less you can afford to let language get in the way. Informal language is the athletic clothing of ideas. [0]: http://www.paulgraham.com/talk.html

Eh, I suspect part of the reason is that once a topic crosses a certain level of difficulty, trying to convey an exact explanation for it in a reasonable amount of time becomes impossible and experts just fall back on analogies and hand-waving.

I'm a physicist, and if you asked me to explain Newton's laws or classical thermodynamics to someone, I could probably give them a reasonably complete overview in a few hours. And in doing so I'd probably introduce and explain some jargon (entropy, derivatives, etc) along the way to make it easier.

On the otherhand, if you asked me to explain Quantum Field Theory or General Relativity in the same time, I'd basically just give up and throw out some friendly but inexact analogies about stretched rubber sheets and the like, and hope the walked away with some vague sense of the outlines of the subject.

Re: If you can’t explain something in simple terms, you don’t understand it

#65

Feynman also said: "Hell, if I could explain it to the average person, it wouldn't have been worth the Nobel prize." [1] Showing a limitation of the maxim or Feynman's hubris? [1] https://en.wikiquote.org/wiki/Richard_Feynman

Not hubris. Feynman won the Nobel Prize in physics in 1965. Here's his Nobel Prize lecture.[1] This gives some insight into how he thought.

[1] http://www.nobelprize.org/nobel_prizes/physics/laureates/196...

Re: If you can’t explain something in simple terms, you don’t understand it

#66

I can simplify how a car engine works, but that doesn't mean I understand how the air to fuel ratio is obtained. Opposite example: Simplify how walking works, and make sure to include the critical systems such as major muscle groups, stabilizers, vision, inner ear, thigh/knee/pelvis/hip construction, the curved spine and its connection to the head, and blood pressure flow/regulation.

Still, you understand how it works. Is it enough to build one? Of course not.

You'd be missing a lot of experimental data that has been collected for decades. You'd be missing the metallurgy, etc.

The basic principle is very simple. Maybe you could even build a low powered version, given materials and time.

If you insist that understand how to obtain the proper air to fuel ratio is required to understand how an internal combustion engine operates, then I'd say we don't really understand anything at all. Can you mine and refine the ore to create the allows it is made of? Can you program the ignition (or alternatively, build a carburator)?

We all need to stop at some point.

Re: If you can’t explain something in simple terms, you don’t understand it

#67

The problem I find with this outlook is that it takes technical terms being jargon at face value. If you can't fall back on progress in language which allows you to express more complex ideas, you're not going to reach the same depth of understanding in simpler words without it taking a lot longer anyways - with most of your time spent reestablishing what you just threw out the window. If you rehash it in smaller wor…

Well, yeah, but the technical detail doesn't have to remain low. When you first explain something to someone you keep it simple so that they get the broad picture, you use analogies and what not. As they learn you can start introducing more and more detail.

It's about explaining in a way the recipient can understand so "simple terms" becomes "terms your recipient can understand".

Re: If you can’t explain something in simple terms, you don’t understand it

#68
This strikes me as raw arrogance. Complexity is intrinsic to many systems that are subject of expert study. To tell someone who has devoted their career to understanding a complex topic that they don't understand their subject because they can't express it in layman's terms without doing terrible violence to the underlying phenomenon is ludicrous.

This is the sort of thing you'd believe if you were an arrogant 20-something who thought they could learn any subject in a few hours, cushioned thoroughly by the illusion of understanding.

"Oh yeah, I understand the mechanisms of human vision. It's just rods and cones."

"I understand the causes of the American revolution. It was just people protecting their property."

"I understand Joyce's Ulysses. It's just follows three people from Dublin over a single day. I read the Cliffs notes."

"I understand why coffee makes me alert. It's just blocking some brain things that make you sleepy."

Now, I will agree that if you don't know how to break interactions down into teachable parts, you will probably have trouble as an engineer or scientist both advancing your own knowledge and introducing people to the field. But to suggest that your understanding of a subject hinges on being able to deliver an explanation in simple terms is just silly.

Re: If you can’t explain something in simple terms, you don’t understand it

#69
Nassim Taleb makes a convincing argument that you first understand something implicitly and then later it becomes formalized. I'm not sure I buy into the idea that people with great communication skills have privileged understanding. The underlying assumption here is that understanding is verbal. I reject that hypothesis.

Re: If you can’t explain something in simple terms, you don’t understand it

#70
post #12

The problem I find with this outlook is that it takes technical terms being jargon at face value. If you can't fall back on progress in language which allows you to express more complex ideas, you're not going to reach the same depth of understanding in simpler words without it taking a lot longer anyways - with most of your time spent reestablishing what you just threw out the window. If you rehash it in smaller wor…

> If you rehash it in smaller words, just by information density alone, aren't you guaranteed to be losing some detail? Of course, but when explaining something to another person, one should strive to optimize for being understood, not for the highest information density.

This discussion really needs a concrete example.
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