People have said you don’t understand something until you’ve taught it in a class. The truth is you don’t understand something until you’ve taught it to a computer, until you’ve been able to program it.
Most of the quotes I pick are on this blog because I agree with them. George Forsythe was the founder and head of Stanford University’s Computer Science Department so he certainly has standing to comment on teaching methods, but I think that this quote underestimates the usefulness of teaching a class to other people. Teaching a computer is useful, it forces me into many corners that I wouldn’t have to explore and exposes my misconceptions; however teaching a class exposes me to other people’s misconceptions, many of which end up not being misconceptions at all. At the very least, they point me towards a different way of thinking about the problem.
Teach it in a class and teach it to a computer.