Not every part of your ideas need to be novel and unadulterated by the rest of human progress. If your ideas need to fit in to some wider context (e.g. you need to produce working code) then it is very helpful to be able to look up important facts about that wider context rather than guessing.

If looking up helps you catch a misconception or missunderstanding about the real world, it's great.

I find it very hard for external sources to support my thinking (if they do I don't read them but save for later comparison). If anything they prove me wrong when I am on the wrong path.