Astrology IS a Load of Rubbish
By Keir Liddle
Prof. Brian Cox, presenter of numerous Horizon documentaries, and the excellent Wonders Of The Solar System, has recently come under fire for stating the obvious: Cox rightly proclaimed astrology to be a “load of rubbish”. Unfortunately, this appears to have upset quite a few people who seem to hold on to the idea that astrology is a valid science.
The belief that the planets, stars and other heavenly bodies can have a “profound influence on our planet” is not all that wild a claim (any astronomers out there will likely be able to clarify). However, surely astrology relies on these heavenly bodies having a profound influence on us? Now, this is a wild claim, and one which doesn’t stand up to scrutiny.
There are known to be four forces in the universe: gravity, electromagnetic force and the strong and weak nuclear forces. The latter two work on the subatomic level, so we can ignore them with respect to this argument. That leaves us with two forces with which the heavens can influence us: gravity and electromagnetic force.
The electrical charge of most of the planets is negligible. Venus, Mars and Pluto (although Pluto is now a dwarf planet, it is included here for tradition’s sake) have no magnetic field, and Mercury has only 1/1000th of the Earth’s field. Only gas giant Jupiter can hold its own against the Sun, with a field 20,000 times stronger than Earth’s, overtaking Saturn at 500 times stronger, Uranus at 50 times stronger, and Neptune at 30 times stronger. How much influence could these planets exert on us?
Well, the farther away a planet is from the Earth, the weaker the strength of its influence on the Earth. Magnetic field falls rapidly – it is inversely proportional to the square of the planet’s distance from Earth. These planets are so far away from us that any influence their magnetic fields might have is countered by the influence of the Earth’s own magnetic field. Indeed, their effects are entirely negligible. The same is true of the effects of the gravity of the other planets: almost all the effects are less than 1 billionth of the effects of Earth’s gravity.
In terms of forces that might influence human beings, the Earth influences us a lot, lot more than distant planets, and other bodies in space have the capacity to. The electromagnetic force of an electric razor influences you 16 million times more than that of Jupiter when you are shaving and if you Stand next to a 80,000 lb truck it exerts a gravitational influence on you 300 times more than Mars.
Astrologers may try to convince us that they produce birth charts, and predictions that are accurate. In reality, astrology has failed rational scientific test applied to it. People may think their predictions are accurate in much the same way that they might assume that psychics can communicate with long dead loved ones: we are biased towards noticing the hits and ignoring the misses. We read a horoscope and notice the bits that might apply to us. Later on, we may associate what’s in the horoscope with events we have experienced, ignoring the parts that didn’t come true. There is perhaps a degree of self-fulfilling prophecy in this.
Horoscopes can also be convincing if they are composed of Barnum statements (also known as the Forer effect): statements that are vague enough to apply to anyone, but appear individualised and specific.
In 1948, psychologist Bertram R. Forer gave a “personality test” to his students. Afterward, he informed them that they were each receiving, based on the test’s results, a unique personality analysis. He then asked them to rate this on a scale of 0 (very poor) to 5 (excellent) on how well it applied. In reality, each had received the same analysis:
“ You have a great need for other people to like and admire you. You have a tendency to be critical of yourself. You have a great deal of unused capacity which you have not turned to your advantage. While you have some personality weaknesses, you are generally able to compensate for them. Disciplined and self-controlled outside, you tend to be worrisome and insecure inside. At times you have serious doubts as to whether you have made the right decision or done the right thing. You prefer a certain amount of change and variety and become dissatisfied when hemmed in by restrictions and limitations. You pride yourself as an independent thinker and do not accept others’ statements without satisfactory proof. You have found it unwise to be too frank in revealing yourself to others. At times you are extroverted, affable, sociable, while at other times you are introverted, wary, reserved. Some of your aspirations tend to be pretty unrealistic. Security is one of your major goals in life. ”
On average, the rating was 4.26, but only after the ratings were turned in was it revealed that each student had received identical copies assembled by Forer from various horoscopes. As can be seen from the profile, there are a number of statements that could apply equally to anyone.
These statements later became known as Barnum statements after P.T. Barnum, who used them in his performances, allegedly stating “there’s a sucker born every minute”. This, if he had said it, would be reference to the fact that Barnum statements can gull people into thinking that they have been accurately assessed by the speaker or test, when in fact, the outcome could apply to anyone.
I think the astrologers owe Professor Cox an apology, and should perhaps admit that they have been rather starstruck.