Here's something I realized last year: it's OK to be vegetarian because you don't like the idea of killing animals.
For much of my life I've had two reasons for being vegetarian: a real one and a fake one. Here's the real reason: there was a moment when I realized that chicken (the food) and chicken (the animal) were the same. After that, I couldn't really stomach the idea of eating meat. So began my slide into vegetarianism.
I also had a fake reason, because it's uncool for teenage boys to dislike killing animals. In school, I'd my friends that "if I'd killed this animal in the savanna after a three day hunt, I'd eat it gladly; that's just nature." Then I'd say, "but modern factory farms are gross and unethical, and I don't want to fund an industry like that" and everyone would nod politely. I was never sure whether the first part was true. But the answer saved face, and over time I really came to believe it.
I finally stopped telling the fake story last year. I wish my realization was that you should say what you believe, even if other people think it's dumb. Actually my realization was that the "it's just nature" argument is stupid. Humans also kill and steal in nature. Just because something happens in nature doesn't mean it's good.
With that argument out of the way, I was finally able to clearly see that I'm vegetarian because of an emotional moment I had when I was ten. And after some thought, I decided to continue being vegetarian.
My reasoning goes something like this. Young children have access to a uniquely raw moral compass. Groups of adults can be socialized to believe almost anything. But young children haven't been around long enough to have their innate idea of morality reshaped by society. Their moral compass might be unrefined and imprecise, but it also seems accurate and unbiased in a way that's hard to achieve after living for many years in a society that tells you what's moral and what's not. So we should pay special attention to cases where young children consistently express moral views that differ from society's. That's one of the ways we can notice things that seem normal now, but will seem barbaric in 200 years.
I think eating animals is one of those cases. Lots of children freak out when they realize that the animal whose ears they're stroking at the zoo was on their dinner plate last night. Children seem to share an understanding that killing animals is bad.
And it's not only children. Lots of people, even as adults, can't stomach the idea that the piece of meat on their plate used to be an animal. They have to shut it out of their mind while they eat their quarter pounder. I can't stomach the idea either. And that's an OK reason for me not to eat meat.