Labels on canned goods are a good thing. They provide a lot of information you need--what's in the can, how much is in there, whom to sue when you get sick.
But with people--we know not to judge a book by its cover, right? Was it Kierkegaard or Dick Van Patten who said, "If you label me, you negate me?"
People are complicated. Liberal, conservative, moderate; Catholic, Sikh, atheist (maybe I should capitalize that to give it more gravitas); straight, gay, bi; big-endian, little-endian, vegan; capitalist, Nazi, Stalinist; pro-life, pro-family, pro-choice; environmentalist, clean coal advocate, BP stockholder.
When I was a kid, the Department of Health, Education and Welfare had a PSA that must have run during Saturday morning cartoons, because--like the Preamble to the Constitution (props to Schoolhouse Rocks!)--I can recite it by heart. An old man and his grandson are fishing in a rowboat on a quiet lake. Gramps calls out the kid for being a bigot--do you remember this? "Jimmy is one of my Jewish friends." "Well then, you are prejudiced. You think of Jimmy as your Jewish friend, and not your friend."
Sometimes, people do you a favor by telegraphing their own prejudices*. For instance, "I'm not a racist, but . . ." has never in the history of mankind been followed by anything but a racist comment. Most Facebook postings using the plural "liberals" or "conservatives" telegraph the writers' prejudices (and fondness for straw man arguments).
But like life, like people, using labels is complicated. If I have a vegetarian over for dinner, I know I should make some meat-free foods. If I'm having a happy hour and invite a Mormon friend, it's hospitable to offer Fresca and root beer in addition to margaritas and microbrews. Labels aren't all bad.
Maybe the point is to start with the cover, then look deeper into the book. Or maybe the point is that it's really not our place to judge human volumes at all.
*Also be wary of any statement following the words, "I'm gonna be honest with you," or "Trust me," or "Of course, you know that . . ." People rarely argue with "Of course." Trust me. I use it a lot, to be honest with you. Check the first line of this entry.