> This is a common problem I find in mathematics, where someone never learned one key element, and struggles to pin down why everything is so difficult for them

> This is a common problem I find in mathematics, where someone never learned one key element, and struggles to pin down why everything is so difficult for them. Reminds me of Ben Orlin's "law of the broken futon": a single missing part can, over time, warp an entire futon and render it unusable. https://horizonsaftermath.blogspot.com/2016/02/the-law-of-broken-futon.html https://horizonsaftermath.blogspot.com/2016/02/the-law-of-br...