Astrology is nonsense

Astrology is nonsense
12 September 2014

I’ve received several questions about astrology and I thought that I could dedicate this vlog to explain why astrology is nonsense.

Astrology is the belief that the apparent position of some astronomical objects in the sky at the time of birth influences a person’s character and can predict their future.

There are many reasons why astrology is not real, so let’s analyse a few.

Western astrology was born in the third century BCE and it is a mixture of Babylonian and Egyptian astrology mixed with Hellenistic beliefs. Using the position of the sun and the planets in relation to special constellations, they construct natal charts to make predictions, these are what we call “horoscopes”.

These charts are what astrologers still use to make daily horoscopes, and they’re based on a Universe where the Sun and planets orbit around the Earth and only five planets exist. Belief in astrology implies a belief in having the Earth at the centre of the Universe.

My second point is related to the zodiac. Constellations are mostly made by independent stars that carry the resemblance of a real life object. This phenomenon is called Pareidolia and it’s the reason why this gas canister looks like a grandma caterpillar applying lipstick.

grandma caterpillar putting on lipstick

Stars in constellations are very far apart, and if we change our point of view the entire designs and meanings we have given them cease to be correct. With your naked eye and great conditions one can see about 3000 stars in the sky. In our galaxy alone there are 100 billion stars. And there are 100 billion galaxies in the known universe. So, there’s no reason why this handful of stars should be in anyway special in the great scheme of things.

Another logical fact that disproves astrology is the relation between any human and other bodies in the solar system. Followers of astrology believe that the planets influence our lives, so scientifically speaking they need to exert a force on us. I’m going to quantify it in a second, but just so you know the force that a planet (or even the sun) exerts on you is the same as the force you exert on them. Let’s pick the Sun, since it’s the biggest object in the solar system holding 99.86% of its mass. So, the force for a 70 kg person is equal to 0.431 Newtons which is 1700 smaller than the force we receive from the Earth. How about Jupiter: the biggest planet of the Solar System? Even at its shortest distance from Earth, the force Jupiter exerts is 10^32 times smaller than the force we get from the Earth.

Lastly, and ironically, astrology has no predictive power. I’m not simply talking about the ability to divine the future, but the ability to explain phenomenon we see happening.

For all scientific disciplines to be considered valid they need to possess predictive power, and I would argue that a good deal of predictive power needs to be involved in the arts too. Not simply technical predictions, if I mix yellow and blue paint I get green, but also the ability of an artist to transmit a certain emotion with a play, a story or a sculpture.

Astrology can’t do that. Astrology doesn’t have an explanation on why planets and stars influence humans, historical events or the weather. It has been proven in several studies, such as the experiment conducted by Zarka in 2011, that astrology is equivalent to random chance when predicting events or personalities.

I can hear people arguing that they only check the horoscopes ironically and that it’s just harmless fun. But it’s not. A member of the British Health committee, David Tredinnick wants to use astrology in the National Health system. He wants to use nonsense to cure people!! Even smart people don’t often realise that astrology is completely fictional. I was at a party surrounded by medical doctors, and being the odd doctor out they asked me about my PhD. Eventually someone asked me if I believed in astrology. When I went on about all the reasons why it’s garbage they interrupted by saying “Why does it matter if people use astrology in their lives?” I rebutted “Would you use phrenology to diagnose a patient?” And they looked at me as though comparing a discredited medical practice to astrology was like comparing apples to planets.

If people that have power over other peoples lives make decisions based on daily nonsense written by frauds, then they need to be educated.

Although I understand the evolutionary need behind the belief of a written destiny, I can’t quite understand why anyone would pick something like astrology, which has been debunked for 400 years, especially since it requires the believer to relinquish the ability to make their own choices in life. Maybe it would be easier to blame my many mistakes on a supernatural force, but I’d own them as mine, like my few successes. Shakespeare said it first: the fault, dear Brutus, is not in our stars but in ourselves.


Zarka, Philippe (2011). “Astronomy and astrology”. Proceedings of the International Astronomical Union 5 (S260): 420–425.