Astrology ... I'm not impressed

What do Nicolai Copernicus, Johannes Kepler, Tycho Brahe, and Aldous Huxley have in common. The first three are famous medieval astronomers and the fourth is the grandson of Darwin's Bulldog, Thomas Henry Huxley. So one answer to the question might be an inordinate interest in science. But another answer would be a confirmed belief in the validity of astrology.

I find this interesting. Science is most rational activity that humans engage in. It looks for natural mechanisms underlying natural phenomena. By understanding these mechanisms we can generalize them and make accurate predictions about outcomes that are often surprising. For example, the computer I am using as I type up this blog owes its existence in a very real way to quantum mechanics. Quantum mechanics tells us exactly how transistors work. This computer has millions of transistors on microchips.

Copernicus, Kepler, and Brahe were all great scientists. Their work led to heliocentric theory of the solar system ... a theory that allows us to predict with fantastic accuracy the position of all the planets in the night sky. Without that knowledge gravitational theory would never have gone beyond apple-falling-from-the-tree stage. These guys appreciated natural mechanisms.

So what is the natural mechanism underlying astrology? How can positions of planets affect people based on their date of birth? Just thinking about it it should be obvious that there is no mechanism which can mediate the phenomenon. Perhaps Copernicus, Kepler and Brahe could be forgiven because the basic forces underlying the universe were not well understood at the time.

But Huxley should have known. His grandfather was one of the greatest naturalists in history. His brother, Julian was instrumental in unifying Dawinian evolutionary theory with modern genetics. His half-brother, Andrew, was a Nobel Prize-winning neuroscientist. But Huxley for some reason gave credence to astrology and other "spiritual" phenomenon with no plausible mechanism.

Why? That is what I find interesting. There seems to be desire to believe things that we have no reason to believe. It exists today. According to a recent Harris Poll 30% of adult females and 19% of adult males in America believe in astrology.

I often hear it said that you can't reason a person out of a belief that he didn't use reason to come to believe it. That sounds pithy and intuitively correct. But what is the alternative? What other than reason will convince a person of the unreasonableness of a belief?

Not only is it obvious that there is no mechanism that can possibly mediate astrological claims, there is empirical evidence that astrology doesn't work. Sometimes you can find that evidence in unexpected places.

OKcupid.com is a popular dating website. They have over 500,000 users. Users enter information about themselves. Much of it is their likes and dislikes. But some of it includes things like their astrological signs. The websites uses a program to match likes and dislikes. The higher the correlation the more likely people are to be compatible.

The website also has a blog that publishes some of the data. Typically, compatibility scores range from 75% (highly compatible) to 45% (highly incompatible). The average score between any two people is 60.2%.

If as many people claim, certain astrological signs are more compatible with others, then OKcupid's data should show it. Some astrological signs should be higher than normal and some should be lower than normal. If astrological signs have no effect on compatibility then all signs should be about normal ... about 60%. Here is the data:

That is about as clear cut as you can possibly get. But somehow I am afraid that there will be some people who insists this shows Aquarians should NEVER date each other.