{Originally published, with comments, in the Coloroado Springs Gazette, January 19, 2011}

Stop the presses! Your zodiac sign is wrong!

Every few years, when someone bothers to ask real questions to a real scientist, the question of “precession” and astrology comes up. This happened recently in the Minnesota Star-Tribune. Now the blogosphere is all a-twitter with yahoos who can’t face their book of astrology being wrong. Sigh.

The latest online Storm in a Sagittarius concerns the notion of precession, something that real scientists have known about for centuries. The earth wobbles on its axis, which over thousands of years changes the apparent location of celestial bodies in the sky. In a few millennia, for example, Polaris will no longer be the North Star. This apparent movement of celestial bodies causes major problems for astrology.

For example, suppose you were born between the end of March and the middle of April. If you believed in astrology, you’d say that you “are” an Aries. That’s because a couple of thousand years ago, when astrology was first dreamed up, the sun was “in” the star group now called Aries the Ram. Today, however, the precession of the earth’s axis has changed things. You may have thought you were an Aries, but in fact chances are the sun was in Pisces when you were born. Feel like a new person?

The invalidity of astrology isn’t a matter of opinion on which reasonable people may disagree. It has been tested and proven wrong on multiple occasions. No astrologer or group of astrologers has ever done better than chance in a double-blind protocol. In other words, you could have thrown dice or used squatting chickens. The results would have been the same.

Things didn’t have to turn out that way. We could have been living in a universe where astrology worked, in which case those tests would have turned out positive. It just so happens that we don’t, so the tests turned out negative. That’s just how it is.

Why am I so hard over on astrology? What’s wrong with letting people have their fun, if it gets them through the day? Who am I to judge?  Isn’t criticizing people’s deeply held beliefs a bit, well, obnoxious?

I suppose, when you get right down to it, that it is. And I don’t like alienating people. But belief in astrology is symptomatic of a much larger problem in America: A lack of interest in critical thinking.

Critical thinking doesn’t require a PhD, or even a college education. It simply means getting in to the habit of asking “What’s the evidence?” And if the evidence can’t be distinguished from wishful thinking or making stuff up, then you say “That’s wishful thinking” and “You’re making stuff up.”

If people started taking critical thinking seriously, belief in astrology, foot reflexology, homeopathy, crystal power, dowsing, faith healing, demonic possession, the Shroud of Turin, ghost hunting and young-earth Creationism would disappear overnight, freeing up an enormous amount of wasted time, effort and resources. And think of what more critical thinking would do for our politics. It boggles the mind.

What can be done? There are signs of hope. Some newspapers now run disclaimers over their horoscopes, listing them for “entertainment purposes only”. Journalists are the most skeptical people on the planet, so it makes sense that newspapers should lead the way. For online media, try this. For every web site you find that asks for your zodiac sign, write the webmaster and ask for a 13th option: “Astrology is bogus”.

Are you a high school teacher? Propose a critical thinking elective in your school curriculum. Put a critical thinking block in a philosophy or psychology course. Are you a parent? Ask your principal where critical thinking skills are taught. Watch James Randi’s “NOVA” special where he distributes devastatingly accurate horoscopes to a room full of awestruck students. (I won’t tell you how it ends, but it’s easy to find online).

Sure, in the grand scheme of things, astrology isn’t that big a deal. But we’ve got to start somewhere. No need to take my word for it.  Check out the evidence for yourself.