But how do you know what you "ought" to be doing right now?
Your personal values, your boss's orders, etc.
And how do you know what information is useful without collecting as much as possible? Many great advances came from inspirations drawn while not actively thinking about the problem at hand, because they saw a connection between two things that didn't seem connected.
You don't; not for sure, at least. That's part of the problem. It's always possible that you'll somehow benefit from reading one more thing, but if you spend all your time reading, you'll (tautologically) never do anything else.
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