Comment by glhaynes

I think that your point about learning being easier when you've got a problem is probably true. But as someone without such a problem immediately at hand, I could really use a list of interesting problems to give me a starting point. And, even if I had a problem I wanted to solve, I expect I might not even know where to begin on it (so then I'd have two problems, as they say). So in practice I'm not sure what to do with your advice.