I think of vegetarianism as a form of zoocentricism. Animals are more similar to us than to plants, therefore we can empathize with them more readily. Just because your guru told you that you may be reborn as a cow, don't assume you won't be reborn as cauliflower. Sure, science suggests that plants don't have emotions, but guess what, science suggests that animals don't have emotions either (albeit this position is changing). We have evolved to eat meat. If you doubt this, try to get a sufficient compliment of B-12 (necessary to produce hemoglobin)from beans and pasta. If people weren't so against genetic engineering, we could be growing meat that could be eaten without slaughter, without suffering. Also, I would like to point out that maintaining fields for agriculture kills a lot of animals, and destroys the ecological system that was in place prior to cultivation.