Fans dislike or dismiss Ishy because of his madness, but he's always seemed like a complex character with an interesting perspective to me. He's the only one who seems to know the truth about the wars, and to support the destruction of everything (which, as others have said above, could be considered to be a good thing depending on one's opinion). He doesn't seem to be fighting for his own personal gain in the way many others seem to be. Of course, he is rather mad, and nihilistic views could certainly be considered a kind of madness, too (Rand in TGS chapter 1?).

This makes me wonder something - could the following be a theme in WoT? We see numerous references to there being a price for knowledge (mostly with the Finn), but I see Ishy's situation as being comparable to the Aiel discovering their origins. Both have had to deal with some world-shattering revelations about not just their own lives, but about everything they know and believe, and WANT to believe, and have for their entire lives (and generations before!). Some of the Aiel took drastic action and did some crazy things. Could Ishy's 'madness' be the result of his knowledge? Once discovered, these things can't easily be forgotten; maybe he's not so much mad as dealing with the truth in the best way he can - accepting it.

I mean, I think Ishy's super awesome and all, so yeah. And when I think about it, if I knew what he did (and, well, I guess we all sort of do), I can't say I'd do things differently from him. Except avoid confronting Rand directly, of course!