Skeptical Zen 102: pattern matching
Human brains are build for pattern matching. Suppose your brains often sees that A and B occur together. So when it detects A, it will expect that B will be there too.
[Warning: standard boilerplate evolutionary just-so story. For illustration purposes only.] Many times this works, especially historically. A person sees a large furry thing with brown fur in the jungle, and those features are pattern matched into the category "lion", and then RUN. If it's not really a lion, oh well. Maybe that person gets a little embarrassed from running from an old fur coat. If the person doesn't pattern-match a lion, and it is one, well, then there won't be many offspring from that branch of the family tree.
But pattern matching can also cause problems. We all know about political parties. The Democratic party has their party platform: they (say they) are, for example, for legalized abortion, for gay marriage, and for raising taxes on the top few percent of Americans and businesses.
The Republicans have their own platform. They (say they) are for a balanced budget, for not bailing out giant corporations, and for the right of individuals to own guns.
Socialists criticize free-market capitalism, and want the government more involved in health care, among many other things.
All of that is well and good, I suppose. Each party has its list of topics it cares about and believe in.
The problem comes in when you apply human pattern matching. If you heard me talk about legalized abortion and taxes on "the rich", your brain would complete the pattern and place me in the "Democrat" category and mentally say "He probably loves Barack Obama, too!" as well as apply a long list of Democratic party platform beliefs to me, most of which I don't warrant. However, if you heard me talk about some other issues, you'd pattern-match me into the "Republican" category and stick me with some long list of beliefs I didn't earn either. And so on.
It's an extremely easy trap to fall into (myself included). You become used to seeing a behavior or belief associated with another, so you come to expect them both whenever you see either one or the other, even when it's just not there.
So someone says "I support the rights of individuals to own firearms", and that statement is pattern-matched into "I am a reactionary conservative gun nut!". Another person says "I think we need to enhance regulations on firearms" and that is pattern-matched into "I am a liberal fascist wanting to take your guns!" Another person might point out the obvious fact that starting out rich is a much better indicator of future wealth than rugged individualism and hard work, and that might be pattern-matched into "I support socialism/communism!!".
Do ask. Do find out. Or let it remain unknown.
Just.. don't assume.