After having the unfortunate experience of biting into a chili masquerading as basil in my Ka-Pow Chicken, and suffering through the following 5 minutes while I proceeded do drink at least a gallon and a half of water (I'm gonna be up all night), a question came to me: What is it about chili's that provide the burning sensation? Is it an acid? microscopic particles (like poison ivy)? chemical agent? nerve agent? Anybody know?