I liked this quote in a post by Mike Johnston on The Online Photographer:
…I believe it’s still important to get to know a few artists or authors well, and study at least one subject until you’re closer to an expert than a dilettante, and follow a few stories until you’re confident you know what really happened. Knowing one thing in depth gives you insight into how much there is to know about all the things you don’t have time to learn about.
(My emphasis, the previous sentence there for some context.)
Being aware that there’s lots you don’t know is so important. It’s best to know that stuff of course, but knowing that you don’t know it is still better than not knowing you don’t know it. If you know what I mean.