> If you can't explain things to other people, do you really understand it yourself?

I hear this said every now and then and I don’t think I agree with it.

A lot of knowledge builds on other knowledge. And the other knowledge might be required in order to understand the knowledge that one wishes to share.

So then either you have to explain it all, or you will have to simplify dramatically.

Few people will want the full explanation — it would take much more time to explain than they would ever want to spend listening. And I am not saying that to criticize those people. The same goes for myself — there are very many things I wish I could understand deeply. But there simply is not enough time. Specialization is necessary. We must pick the few things that interest or have the most use to us, if we wish to have a chance to truly understand any topic deeply at all. And even in the topics we choose there will be a lot of subtopics that we won’t ever have time to understand as fully as we would desire.

Even if they did want to listen the amount of information could be so huge that it might take several years to explain all of it. And so it can’t be done.

So instead we have to simplify. A lot. Unfortunately, when we simplify we often end up skipping crucial information and might even communicate the knowledge wrongly. In the cases where at least we don’t communicate it wrongly there is still a significant risk I think that one or several of

- the truth,

- the value, and/or

- the utility

of the knowledge we try to share is not possible to see without a lot of context that would take too much time to explain.

I have seen time and time again other people jump from

- the fact that someone was unable to explain something in a satisfying way

to

- concluding that the person that tried to explain it doesn’t himself/herself understand it

When really I think the real conclusion should instead be that it is impossible to determine at that present time whether what is being said is correct. But that neither means that the other person doesn’t know, nor that they do know!

I think the fundamental problem is that we keep insisting that things should be simple when the reality of the matter is that they just aren’t. Or perhaps there is some simpler answer but the only path known by the person to understanding the knowledge they possess is based on the knowledge they learned before they learned the knowledge in question. Then it could be possible for that person to boil it down to something that does indeed both hold truth and is simple to explain. And perhaps that it is what it means to understand something at the deepest possible level — to have the explanation worked out so that it builds on the fewest and most simple prior knowledge required. But to sit down and make those simplifications could also take years. And unless it is the job or the desire of the person holding the knowledge to spend all of that time they could spend on other things just to work out the simplest possible explanation of the knowledge then it won’t make sense for them to do so.

There are a few things more I would like to say about my thoughts on this too but I think this comment of mine has probably turned into a big wall of text already. So instead I will conclude with saying that I think that the ability of one person to explain something to someone else

- relies on their own understanding yes

but

- it relies to a much greater extent on the amount of knowledge that both parties already share

and

- a lot of things in daily life builds on things we all know already, and does not extend it too much, so it is quick to explain and simple to understand

but

- some knowledge is so far removed from shared knowledge, at least by the path to it known by the person trying to explain it, that it is for all practical purposes impossible for that person to explain to the other