[teacpde]

> (1) Learning something deeply is necessarily a lot of work. It’s not like you’re just answering “what is X.” You’re asking ten questions about it, each trying to get at it from a different angle, and then asking ten questions about each of those underlying concepts. The bottleneck to knowledge then is not so much ability, but effort.

This is the truth and it makes me struggle when I want to learn something but not so deeply. When learning a new concept, I often find myself dfs the tree and end up somewhere very far in a single branch without gaining the comprehensive understanding of the concept.