Optical Illusions

I just happened to be led to this webpage on this day of nearly random browsing. Some of the illusions that keep floating around in countless emails are explained here. Hope u guys enjoy this as much as I did. I am truly intrigued by perceptions of reality especially visual perceptions. But in general, the philosophical notion of separatism between truth and perception intrigues me!!!!

http://www.ritsumei.ac.jp/~akitaoka/index-e.html