polymathematic: math that answers why

What it is

polymathematic is a math account with 236,000 followers and a bio that just says "Making math". It is run by Tim Ricchuiti, who also has a YouTube channel of the same name. The videos are built around the "but why?" questions that school usually shut down with "because that's the rule".

Recent examples: how the empty product, a multiplication with no factors at all, explains a whole bunch of otherwise weird results; whether we can say something better about zero than "because we said so"; associativity, the case where regrouping really does not change the answer; and a neat analogy about getting dressed. You cannot put your shoes on before your socks, so why does math class keep insisting that order does not matter?

Why we picked it

This is math as a way of thinking, not a list of rules. Tim takes things everyone memorised and shows where they come from. After his videos, a rule that felt like a trick turns into the obvious consequence of a sensible idea.

We like the tone as well. He is calm and friendly, never scary about notation, and he regularly answers viewer questions and picks apart viral math memes. There is no course upsell, just explanations.

Where to start

• The empty product video, the most elegant of his recent posts.
• The socks and shoes analogy, on when order matters and when it does not.
• The associativity video.
• His replies to viewer questions, if you enjoy seeing a problem taken apart.

Who it's for

Anyone who decided at school that they were "not a math person" and wants a second try. Students, parents helping with homework, teachers looking for a new way to explain an old rule, and anyone who enjoys the moment when something suddenly makes sense.

Quick answers

Do I need a math background? No. School arithmetic and some curiosity are enough.

Is it selling a course? No, the videos are free explainers.

Is there longer content? Yes, on the polymathematic YouTube channel.