During a Sunday afternoon run I solve an open problem. I'm a genius.

I get home and put on the coffee. I stand in the door frame basking in my cleverness.

I notice a drop of sweat on the door-frame.  I must have left it there when I momentarily touched my head against it.

Cleverly, I decide that I can get that drop of sweat with my shoulder.  Leaning my shoulder against the door-frame, I jump up to wipe the drop of sweat with it.

Perhaps this was not so clever. Because I'm standing in a low door frame. I jump up and whack my head on the top of the frame. I'm an idiot.

Lying in bed with a sore neck, I realize that I didn't actually solve any open problems.