I'll show YOU kosher!

Realization: I'm not very good at explaining to questioners why I don't mix meat/milk. What's a quick, one-sentence explanation that doesn't edge on "because the Torah says so" ...? I go into a big explanation of a variety of things, and well, I seek brevity.

(Note: At the present, my policy is no goat in goat's milk, no beef in cow's milk, etc. "Thou shall not cook a kid in its mother's milk" to me means just that.)