Several decades ago, I did a degree in electronic engineering. This entailed learning how to use quite a lot of maths—but mostly not learning how to prove the maths. This is a shame because if I'd learnt properly, I'd probably have been more interested in the maths than in the engineering. (Before university, I enjoyed maths when it was a thing one did, and stopped enjoying it when it was a thing one remembered.)

I'm now trying to remedy this by examining every mathematical step or theorem that I have the last doubt about, and where possible, tracing it back to the most basic theorems, axioms and definitions I can.

I'm also trying, as far as possible, to translate mathematical concepts that I'm used to dealing with in symbols into non-technical, non-mathematical language, in order to get right to the core of each concept or underlying argument. So my answers on here are often efforts to explain ideas as clearly and simply as I can, with as little jargon as I can.

Non-mathematical interests include language, music, and psychology of learning—especially as it applies to adult self-education.