Talk:An Under-Edd's-Hat Theory/@comment-98.114.141.54-20130504042258

Any exposed brain tissue or lack of skull covering the brain would be fatal and would not have anything to do with his intelligence, so I'm afraid that theory doesn't work at all.

Random theories that I don't nescessarily believe are true, but just throwin' em out there:

Edd has a polish plait under his hat. Don't know what that is? Look it up... you're welcome. Highly unlikely since they are caused by a lack of hygeine.

Edd has a parasitic twin on his head- definitely something one would want to keep under a hat, and something not easily removed or treated like a tumor or something. Also, it would explain Ed and Eddy's reactions. This also turned out to be Edd's voice actor (Samuel Vincent's) theory as well as the prevailing theory in the early EEnE community.

Edd has trichotillomania, aka compulsive hair picking. Given his neurotic tendencies this trait would be in character for him, as it is a manifestation of anxiety. In severe cases it can lead to bald spots, scarring and infections. Many who suffer from the condition wear hats at all times. Why not just shave his head, then? Because then there'd be no hair left to pull out, and it'd drive him crazy. And while a bald head may not bother anyone in the show, a sickly, patchy hairdo might.

A chemical burn or fire burn scar would make sense as Edd freuently experiments with chemistry which can involve both dangerous chemicals and extremely hot surfaces/fire. Such burn marks can scar permanately and deform the skin, Edd the perfectionist would hardly want something so unsightly drawing everyone's attention so he's been forced to keep it under his hat. Since he had the hat since he was a toddler, though, he'd have to be awfully young... but since he is so advanced in intelligence the idea of him engaing in such things at that age isn't even a stretch, and may explain why, in his naievity, he made such a careless mistake that resulted in the scar in the first place.

Or maybe, Edd just has an oddly shaped scalp. It could really be that simple!