When I started programming I was pretty bad at it. I didn't get good until I focused on "really" learning perl. I mastered perl fairly well quite a few years ag

When I started programming I was pretty bad at it. I didn't get good until I focused on "really" learning perl. I mastered perl fairly well quite a few years ago. At some point I was no longer learning anything from perl and I tackled something different. Erlang was my next deep dive. What Rich is saying has less to do with how many languages you've absorbed whether a lot or a few. What he is saying is that leveling up requires taking the time to truly absorb and understand what you are working with. I'm fairly polyglot these days. But the number of languages that I know deeply is less probably about 3. With the time spent learning them measured in years not months. Peter Norvig is actually saying something similar. He's advocating a slightly different route to the same goal. Learn the foundations of programming deeply. The 4 broad categories he lists are foundations of programming that any developer needs to learn deeply. Both Rich and Peter advise investing the time to learn something thoroughly. They just came at it from slightly different directions. I imagine they would agree with each other though.