[gerbilly]

I agree that we overvalue reason.

To reason about something you have to reason from premises. But where do the premises come from?

I'm sure many of us have had that experience, when dealing with a difficult problem, where an insight comes to us out of the blue.

Where did that new insight come from, certainly not through rational deliberation. In fact, often it's not until we stop reasoning that the insight is free to appear.

Often we can't explain where the idea came from, it seems to be from some subconscious (irrational?) part of our mind.

Once we have the insight (a new premise) then we can start to reason from it. But in my opinion, reason comes in only after our mind has done the real work elsewhere.