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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

#81
post #12

Earlier quoted context omitted.

> 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.

Here is one of the best examples of clear communication I know:

http://norvig.com/spell-correct.html

Norvig is a genius, and his genius is reflected in how he can so succinctly and clearly explain how to write a spell checker, without falling into elaborate jargon or droning on without getting to the point.

And that goes equally for his code and his prose, by the way.

There are many people who use a lot more jargon and verbosity to make their points, who are not in the same league as Norvig in terms of intelligence.

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

#82
post #46

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

It's not just some hard physics that have trouble with the ELI5 / "should be able to explain it" concept. This is also true for literature, poetry, non-analytical philosophy etc. And there the challenges are not about the complexity of the subject, but about its subtlety, and how one needs historical context and/or certain life experiences (or even proclivities) to be able to grasp a particular piece of work.

It's not so much life experiences, but prior knowledge and familiarity.

Taking mathematics as the operative example. A lot of deep theorems are trivial when you fully understand all relevant definitions. These proves cannot be stated 'in simple terms' because it took a stack of non-simple definitions to even formulate such a theorem.

Explaining the entirety of the stack gets hard when the stack gets deep. For example, a lot of math gets really hard to explain when the concept of the real numbers being 'uncountably infinite' whilst the rationals are 'countably infinite' isn't obvious.

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

#83

This is generally true but I will add one wrinkle. And there are three kinds of explanation: 1. visual 2. mathematical 3. linguistic So sometimes, you understand something visually, or mathematically, but you are forced to put it into verbal terms (say, over a text only channel, or voice), and then you may seem not to be able to explain it even though you understand it.

I first learned about The Big Triangle from Scott McCloud's "Understanding Comics".

http://scottmccloud.com/4-inventions/triangle/index.html

http://homes.chass.utoronto.ca/~mfram/Media/0505-UC-triangle...

Filed under "I believe, but cannot prove": The three-way tension is a recurring pattern.

When trying to understand new things, I often try to reframe things as a triangle. When pondering intractable problems, I favor three-way solutions. Some quick examples from memory...

Project management: time, money, scope.

aka Quality: Fast, good, cheap.

US Govt balance of power: Executive, Congress, Judiciary

Language design: imparative, declarative, functional

Pop music: harmony, melody, lyrics

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

#84

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-som…

I strongly disagree.

Complexity is real, but understanding means being able to conceptualize a system at such a high level that it becomes possible to convey the most important key ideas simply. This may involve some amount of over-simplification (which should be indicated if present) and will undoubtedly leave out a tremendous amount of detail, but the conceptual essence should be there.

The inability to do this is IMHO a sign of either lack of true and deep understanding or communication ability.

There are fields where nobody can really do this. These are fields that nobody truly understands yet.

Edit:

Let me give you an example. I had a bad (but typical) math prof in my very first calculus class who covered the board with examples and took us through how to differentiate a function. I was completely confused and stuck. Then I called my father on the phone and asked him and he told me "a derivative is a rate of change." Then I got the rest of calculus.

The prof had talked about slope but that wasn't conceptual enough. I needed "rate of change." That is the essence of calculus. It's the most important concept. Calculus deals with rates of change and the inverse (integrals). Once this concept was communicated the rest of calculus became possible to understand.

If you can't do that for a given area, you don't understand it or (as was the case with this math prof) are a poor communicator.

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

#85
Understanding something is having a good working model stored the way brains store models, which is quite a complex network. Explaining it requires finding a way to serialize it that makes it as easy as possible for a listener to reconstruct the model in his own mind.

I think the effort involved in trying to come up with a serialization causes us to more carefully examine our models, which usually improves them.

But I don't think the lack of a good serialization implies the lack of a good model.

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

#86

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-som…

Have you ever 'taught' anyone anything? When you do, you'll probably get what Feynman was trying to say. Complexity is intrinsic. Just that as a teacher/guide/explainer, you have to gently guide the novices around enough to invoke a sense of curiosity that will drive the pupil to explore on their own. The task at hand here is to make things less overwhelming, not removing or ignoring complexity.

For every complex system, there is usually an underlying simpler, though not accurate, model that makes grasping the broader concepts easier.

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

#87

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-som…

Coffee makes me more alert because it triggers a release of ATP.

I do agree it is arrogance.

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

#88
post #84

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-som…

I strongly disagree. Complexity is real, but understanding means being able to conceptualize a system at such a high level that it becomes possible to convey the most important key ideas simply. This may involve some amount of over-simplification (which should be indicated if present) and will undoubtedly leave out a tremendous amount of detail, but the conceptual essence should be there. The inability to do this is…

> This may involve some amount of over-simplification (which should be indicated if present) and will undoubtedly leave out a tremendous amount of detail, but the conceptual essence should be there.

I think the disagreement hinges on whether you believe the snippets from the GP post e.g. the "rods and cones" or caffeine examples are fundamentally valuable or not.

> There are fields where nobody can really do this. These are fields that nobody truly understands yet.

Curious what you would consider an example of such a field?

FWIW my anecdotal example of what I think the GP is complaining about... I read "The Elegant Universe": https://en.wikipedia.org/wiki/The_Elegant_Universe

It's a good book, and I enjoyed reading it. But over subsequent years I've had growing doubts over the true value of the "understanding" that it provided.

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

#89
post #84

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-som…

I strongly disagree. Complexity is real, but understanding means being able to conceptualize a system at such a high level that it becomes possible to convey the most important key ideas simply. This may involve some amount of over-simplification (which should be indicated if present) and will undoubtedly leave out a tremendous amount of detail, but the conceptual essence should be there. The inability to do this is…

[deleted]

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

#90

Being able to explain something in simple terms is actually REALLY difficult to do. It is a skill in itself. Someone can intuitively understand math very well, but lack the skill to explain it to someone else at all.

I love organizing, simplifying things. Geeks are addicted to complexity. I think it's some kinda machismo thing.

This incompatability has caused me problems my entire career. I've more or less stopped trying. I just do what I'm told and save my creative energy for my personal projects.

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