I don't think that this is what the person you're replying to meant.. For example, say you need to do matrix multiplication. What's more important, knowing how

I don't think that this is what the person you're replying to meant.. For example, say you need to do matrix multiplication. What's more important, knowing how to do it and when to apply it or meticulously doing the whole computation without a computer? I chose this example because it's nothing more than a focus exercise and as the complexity increases, the chance of you making an error increases too. Most people know what multiplication and addition are but there would still be a high chance that they make small errors due to not paying attention. On the other hand if you come across this problem, know that you need to do this now and let the computer do the operation you decrease the chance of such mistakes. The same is true for many other concepts... What's more important, knowing every system call by heart or knowing how to look up their documentation? No, the important part is knowing what system calls are and when you might need them, for the rest it's just about looking up information. The thing is, you can study a lot of things so that you can do them by heart and it's just an exercise of remembering. But if you grasp the logics of something or start seeing patterns etc. that's ultimately more valuable. It's true for learning a language too.. of course you can learn everything by heart but if there are certain logical rules for how certain words are built up, those are more important.