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by kalid 3104 days ago
Shameless plug, I write about math on BetterExplained.com

For each symbol, I try to make an analogy. For "e", for example, I have the notion of "continuous growth". The formal definition is this:

https://betterexplained.com/ColorizedMath/content/img/E_(mat...

"The base for continuous growth is the unit quantity earning unit interest for unit time."

Once you see the role of each part of the definition, the idea snaps into place. I just wrote about it here: https://betterexplained.com/articles/colorized-math-equation...

Hope that helps!

3 comments

Just wanted to thank you for a great job you do on BetterExplained. I was able to understand and put to use some concepts only thanks to your articles, most recently it was Fourier transform. I'd be much better at math if people writing educational materials realized that there are more effective ways to teach (and to learn) than what they had experienced. Thank you!
I appreciate it, thank you! I have a similar wish, hoping more people would share math in the way that truly helps them.
I like that figure you made! Though shouldn't the whole 1/n fraction be red and not just the numerator?
Thanks! So, the red 1 represents the 100% interest we intend to earn; the pink n in the denominator represents the compounding pieces we divide it into.

For example, an approximation of e would be (1 + .01)^100, where the 100% interest had been chopped into 100 separate segments of 1%.

> For each symbol, I try to make an analogy.

Analogies are utterly unhelpful without a thorough understanding of the actual definitions.

Analogies on their own are limited if you don't continue to the technical definition. They are a raft to cross the river.
> ... They are a raft to cross the river.

or rather like net to catch the fish. once you have the fish, you can forget about the net.

this is not far removed from words, which are used to convey meaning. once you have meaning you can forget about the words ;)

edit-001 : fmt changes.

>> ... They are a raft to cross the river.

>or rather like net to catch the fish. once you have the fish, you can forget about the net.

So you can forget about the net ... like a raft to cross a river?! ;o)

When you are a student, rather than a researcher, formal definitions must come first, and intuition can be developed later. Otherwise, you are just allowing yourself to say nonsense.
I worry about the fact that you're being downvoted, because what you're saying is utterly crucial and important. I fear those who ignore it will waste a lot of time with really misguided ways of doing mathematics. The analogy approach works for programming, but it's not applicable to seriously studying mathematics.
I wouldn’t dismiss analogy so easily. George Polya opened my eyes to the power of analogy in math. I can’t recommend his “Mathematics and Plausible Reasoning” enough.
Polya's text was targeted towards researchers and people who already understood the basics pretty well. But I don't think the analogy approach is valid (or at least, not recommended) in the context of this thread, where the parent seemed to assume that the audience wasn't even particularly comfortable with limits. It can be a dangerous and seductively-easy path to go down, is all I'm saying. You're not going to understand mathematics without having a firm firm grasp of the rigorous definitions and by doing mountains of exercises (where it will often be quickly apparent that using an analogy is not sufficient).
I wouldn't worry too much about it. Math students are not the primary target audience of this website. And, if the planets align and someone here actually wants to study math, they will either quickly discover the limitations of an “analogy-first” approach, or quickly fail and give up.
> The analogy approach works for programming, but it's not applicable to seriously studying mathematics.

Why?

Analogies are always leaky abstractions and it's easy to cement an incorrect notion of the subject matter that doesn't account for subtle behavior and edge cases. I do think explaining by analogy is useful as long as it comes with clear caveats, but as an example, if there were good analogies for quantum uncertainty and wave particle duality, or general relativity, people wouldn't find those things eternally perplexing. YouTube has thousands of hours of videos trying to explain GR with elevators in space and trains moving at the speed of light, but if you can't do the math you'll never really understand it. Some things just can't be broken down into concepts that a three dimensional monkey brain can easily understand.
Because in mathematics, unlike programming, you won't get anywhere without actually understanding the topic at hand.