Knowing things is good, but I think the real benefit of a PhD is in developing the skill to learn new things quickly and fill in any gaps as needed. It’s import

Knowing things is good, but I think the real benefit of a PhD is in developing the skill to learn new things quickly and fill in any gaps as needed. It’s important to get practice learning many things in depth but the goal isn’t to become a storehouse of knowledge, it’s to develop the ability assimilate existing knowledge and apply it to figuring new things out. The amount of topics I’ve studied in depth dwarfs this list (and the same is certainly true of its author) but the set of things I could teach a class on today without preparation is much smaller. The important thing is that if I have a problem, I can use the impressions from all I’ve learned before to get a sense of where to look next. My memory isn’t great but it doesn’t matter because I can refresh, learn, and figure things out as needed.