Consistency

How can someone:

...be opposed to euthanasia but in favor of the death penalty?
...be in favor of the impeachment of Bill Clinton but not of George Bush?
...be worried about global warming but fly in a big private plane?
...be in favor of the impeachment of George Bush but not of Bill Clinton?
...be opposed to amnesty for illegal aliens but in favor of a pardon for Scooter Libby?
...be in favor of military intervention in Darfur but not in Iraq?
...be opposed to big government but want the government to control public speech?
...be in favor of banning medical marijuana but opposed to government regulation of cigarettes?
...be opposed to judicial meddling, except in cases where you disagree with the current laws?

Easy. Because people aren't consistent. Sure, you say, each of the examples above isn't fair. They don't match. They don't line up. [Smart people are lucky: they can hold seemingly contradictory ideas in their head while they look more deeply into the facts and make good decisions... it's called nuance.]

We don't eat dessert cause we're on a diet, but we put blue cheese dressing on our salad. We don't pay extra for first class, but refuse to give up a seat to get bumped from a flight, even though the reward is a thousand dollars. We curse the spam that clutters our email boxes but turn around and authorize millions of pieces of junk mail to go out to support our new business.

The local hardware store owner curses the existence of Home Depot but buys his family's clothes at Wal-Mart. The vegetarian wears a leather belt...

Everything is a special situation, everything begs for inconsistency. If all we did was market to computers, life would be a lot simpler, but a lot less interesting.