> One time I heard someone praised as a good teacher. Not knowledgeable, but a good teacher. I objected that if someone is ignorant but a good teacher, does tha

> One time I heard someone praised as a good teacher. Not knowledgeable, but a good teacher. I objected that if someone is ignorant but a good teacher, does that mean they’re effective in conveying their ignorance? Wouldn’t that be a bad thing? No, all that mattered was that he was a good teacher. Maybe the same isn't true of programmers, but for teachers, being knowledgeable and being a good teacher are different, independent qualities. Sure, there's some base knowledge that should be present. But it's absolutely possible to be a good teacher without knowing much beyond the basics. My best teachers weren't the most expert in their respective domain, they were the ones who let me see the world in a different way -- also in maths, and got me excited about the domain. I teach ballet dancing and clarinet to my kids without knowing anything about either. But I know good when I see or hear it, and I steer them in the right direction.