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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

#201

Post by mncharity »

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

And an underappreciated corollary is...

If you want something explained well in simple terms, you have to find someone who understands it deeply.

In the sciences, that means someone who has it as their research focus. Because as you move away from that focus, understanding rapidly becomes ramshackle. Leave someone's subfield, and you might as well be talking with a random graduate student (in that field). And that's hopeless.

Thus many research talks have videos and stories which would nice to have in a K-12 classroom. And most all K-12 education content is incoherent wretchedness.

An old essay of mine: "Scientific expertise is not broadly distributed - an underappreciated obstacle to creating better content" http://www.clarifyscience.info/part/MHjx6 In which a 5-year old with finger paints wants to paint the Sun, but encounters astronomy graduate students.

"I am sorry for the length of my letter, but I had not the time to write a short one." - Blaise Pascal 1657

There's a sad little genre of low-quality science education research that goes: "I tried to teach topic T to students of age A. I taught it . Surprisingly, that didn't work! I've reach the obvious conclusion: students of age A are developmentally unready to learn topic T."

But understanding, while necessary, is not sufficient. At PhD poster session practice, it's often remarkably hard to help candidates develop an "elevator pitch". To clearly understand the core of what they've spent the last n years working on. I'm still amazed by how often one gets something like "wow, now I can explain it to my parents".

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

#202

Post by squeaky-clean »

Retric wrote: post #191
xg15 wrote: post #180

Earlier quoted context omitted.

But I think that's the deeper point of the "if you can't explain it, you don't understand it": Sure, you can write down the equations, but then what exactly have you done? You wrote down some string of characters and showed that it can be derived from some other strings of characters by applying a series of arbitrary-looking rules. By itself, that doesn't tell anything. It's only when you manage the connect formula t…

QM for example has zero relationship with well known phenomena.

Well, from the article

> Feynman was also quoted as saying:

> I think I can safely say that nobody understands quantum mechanics.

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

#203

Post by eksemplar »

freddref wrote: post #13

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

They are both right. Something's can't be dumbed down enough to explain to everyone, but you can always explain the concepts. An example could be comparing an interface to a chocolate cookie recipe, when explaining it to your grandmother.

She'll still have no idea what an interface actually is, but she'll have a good grasp of the concept.

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

#204

Post by Radim »

NumberSix wrote: post #36

This is Feynman from the introduction to his Feynman Lectures on Physics: The question, of course, is how well this experiment has succeeded. My own point of view — which, however, does not seem to be shared by most of the people who worked with the students — is pessimistic. I don’t think I did very well by the students. When I look at the way the majority of the students handled the problems on the examinations, I…

Another example, even more bare-bones, is AI.

We now have programs that "understand" certain domains better than humans. And yet there are no "simple terms" to explain their understanding, reduce it to a neat closed-form formula.

Isn't it a mistake to assume a nice, elegant explanation, a cute human "narrative", must always exist?

"But Radim, the computers don't really understand the domain!". Sorry, a cop out, No True Scotsman fallacy. In what way do they not?

This is crystal clear with Go: the little stories humans have built to deepen their understanding of the game over 2,000 years are irrelevant to a game's outcome. The details and variations are all that matters, and there is no way to reach the computer's level of understanding of the game without understanding the details.

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

#205

Post by xg15 »

throwaway3535 wrote: post #189
xg15 wrote: post #180

Earlier quoted context omitted.

But I think that's the deeper point of the "if you can't explain it, you don't understand it": Sure, you can write down the equations, but then what exactly have you done? You wrote down some string of characters and showed that it can be derived from some other strings of characters by applying a series of arbitrary-looking rules. By itself, that doesn't tell anything. It's only when you manage the connect formula t…

> You wrote down some string of characters and showed that it can be derived from some other strings of characters by applying a series of arbitrary-looking rules. At this point it's turtles all the way down.

No.

That's what it looks like if you only look at the formula. (And why I'd say that formulas are not an "objectively simple way of expressing something*)

If you can somehow keep in mind what the formula is supposed to represent, the operations on characters will let you find some insight about that thing and will stop standing only for itself.

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

#206

Post by cryptica »

The term "simple terms" is subjective and depends on who the audience is.

A popular question to qualify for engineering job interviews is "describe in simple terms what happens when a user accesses a website on the Internet" - The question doesn't give any info on who the target audience is so you never know what level of detail you're supposed to go into. Because this is an engineering question, I tend to go into more detail but after a certain level, you can't really keep it simple because the reader has to understand what things like cache are... Else you will spend 20 pages just writing definitions.

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

#207

Post by Sacho »

outworlder wrote: post #52
mikebenfield wrote: post #27

I think this idea is basically nonsense. Some things are complicated. To "explain" them in simple terms you necessarily leave out a lot of information. If all that information isn't crucial to the core idea, maybe that's worthwhile. But sometimes that information is crucial. Some people look at advanced mathematics or physics and wonder why it has to be so complicated and so full of jargon. It's complicated because i…

It's not nonsense. You are forgetting a very important detail: "explaining". He was not talking about writing a research paper on the simplest possible terms. Rather, about "explaining" a subject. When we are explaining, we always have to deliberately omit details to get the basic idea across, so that the other person can form the initial mental image. Sometimes we also have to resort to metaphors and comparisons fro…

Er, they may be left with a warm and fuzzy feeling that they have some "understanding", but let get them to do some multidimensional analysis and see how they do. The meaning of "explaining" seems just as elusive as the "simple explanations" themselves - once you've heard such a "simple explanation" and have a feeling that you now understand more than you do, what is the objective difference between you-before and you-now? It's my experience, and several professors have confided the same, that the "simple explanations" give students a nice feeling that they "get it", up to the point where they actually try to apply the knowledge and fail miserably. Maybe the explanation then wasn't really "simple", but now we're just shifting the goalposts further into epistemology.

I would tentatively agree that there is a skill which allows you to break down complex subjects into digestible chunks, but that usually depends a lot on the student as well as the teacher(e.g. some people are good at following metaphors, others learn very well from repeated examples, etc), but the outright statement in the topic suggests that there is no such thing as irreducible complexity, which seems ludicrous.

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