Don't have an answer but I love the question, Zach. Maybe when you start talking out loud to the voice in your head, your muse, or when the pictures you paint like those quivering java graphics seem to move, or the music/songs you play/compose dance in colored shapes around the room -- something like that. Best I can come up with.
Regina, Saskatchewan; Canada
I would say at the point of nonsense and perversity. If something makes little or no sense, or is harmful, but someone is so sentimentally attatched to it that he keeps on thinking or doing it anyways, at that point I think it becomes madness.
Small town, Illinois
Jenn, LOL yeah. When you start to talk in your head and you hear someone else answering back. Or you can't define the difference between your thinking wave and your thinking response. Because I usually think and then think of an answer to my question. But if you can't recognize your "thinking response" you'll believe your mad. Sorry about the random jabber. See that's how my mind works. Constantly moving and talking like a 13 yr.old school girl. LOL.
Ess, Good answer. I don't think I could put it better myself.
Wish I could find love.. But all I find these days are superficial fish in shallow waters.
I would suggest that imagination is the base state. Madness might have something to do with the uses to which imagination is put. Having a wild imagination about beds is one thing. Actually stretching limbs to fit the dimension of the matress, or taking a knife and loping those parts off that hang over the edges might be considered madness.
I suspect the madness has more to do with the action than the thought.
I am of course wrong, but it's a place to start thinking.