In case you haven’t noticed the intertubes have descended into a series of skirmishes on the subject of astrology. The whole thing started with an astronomer in Minnesota who pointed out that the constellations move around the ecliptic (that’s the apparent path of the sun around the earth during the year) due to procession of the equinox, which means that a given constellation is no longer where it was two thousand years ago. Mr Astronomer seemed to think that this means that astrologers are stupid because they talk about the sun being in Aries when it’s actually in another constellation. Unfortunately for Mr Astronomer astrologers are well aware of this and in fact it was Hipparchos, who was almost certainly an astrologer, who first discovered procession. Mr Astronomer is actually being an idiot as he doesn’t appear to know the difference between astrological star signs which are 30° divisions of the ecliptic starting at the spring equinox point and astronomical constellations which are join-up-the-dots pictures imagined in the heavens in order to make it simpler for astronomers to find their way around the heavens. A certain amount of confusion is generated by the fact that the astrological star signs are named after the constellations that occupied their positions on the ecliptic about two and a half thousand years ago as the Greeks invented horoscope astrology.

A second front in the wars was opened as two BBC television science presenters started behaving like pubescent public schoolboys who think it is cool to scream out fuck in the middle of a crowded shopping mall and blurted out that astrology is rubbish in the middle of a programme on astronomy that had absolutely nothing to do with astrology.

The result of all this is the claim that astrology is rubbish has gone mega-viral in the intertubes with blog articles on the subject shooting up in cyberspace like the proverbial mushrooms in the forest. I don’t intend to add anything more to the direct debate as my standpoint has been very adequately presented by the excellent Rebekah “Becky” Higgitts here and here and by the equally excellent Darin Hayton here. However in the comments on various blogs a couple of statements/question have popped up that I seriously think need to be addressed. Somewhere on Becky’s post on The Guardian Website a commentator asked:

Do you think we should take phlogiston theory seriously?

Somewhere else another commentator posed the same question in terms of geocentricity both commentators meaning we should no longer take scientific theories seriously that have been abandoned in the mists of history. My answer to the questions is yes we should take phlogiston, geocentricity and astrology very seriously!

My answer is based on a belief that all scientists should learn about the history of science. Science does not and has never progressed by being continually right but does so through being gloriously wrong, again and again. Abandoned scientific research programmes such as astrology, geocentricity and the phlogiston theory made major and important contributions to the progress of science and in my opinion an awareness of this fact is necessary for students of science if they are truly going to learn how the scientific method functions and how science progresses.

The scientific research programme astrology can be defined as ‘the practice of relating the heavenly bodies to lives and events on earth’ (Patrick Curry). Babylonian astrology generated the science of astronomy that is the Babylonians practiced astronomy to deliver data for their astrology. This programme also contributed substantially to the development of the sexagesimal place value number system and algebra both of which the Babylonians used to record and analyse their astronomical data. With the Greeks this combination continued with the most important of the Greek celestial scientist, Ptolemaeus, writing the definitive books in antiquity on both disciplines, the Syntaxis Mathematiké (astronomy) and the Tetrabiblos (astrology), in the latter he divides the study of celestial phenomena into two area the movement of the heavenly bodies (astronomy) and their influences (astrology). As with the Babylonians astrology was the chief motivation for astronomy.

The astronomy contained in the Syntaxis Mathematiké is the product of between seven hundred and eight hundred years of Greek astronomical research but here I shall only evaluate the end product. Ptolemaeus’ astronomy is of course geocentric but as I have said in the past, and will probably repeat many times before I die, geocentricity is a perfectly rational theory based on the available empirical data and is therefore a perfectly reasonable scientific theory. The Syntaxis Mathematiké not only contains the geocentric model of the then known solar system but also the methods of observing and recording that system, methods that continued to be used up into the 20th century. Ptolemaeus lays out the whole of the standard system of recording the position and movements of the heavenly bodies still in use today. He also describes the instruments that were used by astronomers to make their observation up till the invention of the telescope and beyond. Apart from the telescopes he would have felt perfectly at home in John Flamsteed’s observatory at Greenwich at the beginning of the 18th century. Even the telescopes would not have caused him a great deal of problems as in trying to deal with the problems of atmospheric refraction he conducted detailed research into optics, writing the most advanced text on the subject in antiquity, a text used as a model by Ibn al Haytham, the so-called father of modern optics, in the 10th century in the same way that Copernicus used the Syntaxis Mathematiké as a model for his De revolutionibus in the 16th century. As well as laying the foundation for observational astronomy and the recording of astronomical data Ptolemaeus and the Greeks also delivered both plain and spherical trigonometry as mathematical tools indispensable for astronomical calculations. I really don’t think that anybody who takes astronomy seriously should ignore Greek geocentric astronomy, driven by astrology, and the positive contributions it made to the evolution of the sciences.

If we move on to the Early Modern Period a series of new developments starting around fourteen hundred propelled a new astronomical research programme that would eventually lead to heliocentricity, Kepler and Newton the main driving force of that programme was astrology or better said astro-medicine. The concept that the movements of the heavenly bodies also controls sickness goes back to the Greeks and it experienced a major revival in the Renaissance. The demand for more accurate astrological data to improve astrological forecasts led astrologer-astronomers like Peuerbach, Regiomontanus, Apian, Copernicus, Gemma Frisius, Tycho and Kepler to improve and in the end to reform astronomy. Astrology is a research programme that most would love to deny the status of scientific but it was the main driving force behind the astronomical revolution. In a famous comment the historian of astronomy Robert Westman noted that there were only ten Copernican astronomers in the entire world between the publication of De revolutionibus in 1543 and 1600 and as one historian of astrology has correctly pointed out they were all practicing astrologers.

Of course the astrologers of the Early Modern Period were painfully aware that their discipline did not live up to the standards of empirical science that they themselves believed in and practiced and so a number of research programmes were launched to provide the empirical underpinning that astrology lacked, principle amongst these was meteorology. The belief that the heavens control the weather goes back to antiquity and was one of the major sub-disciplines of astrology. In the Early Modern Period astronomer-astrologers such as Johannes Werner and Tycho Brahe keep weather diaries in which they meticulously recorded the weather and the positions of the heavenly bodies. In the end these diaries proved that there was no correlation between the two sets of recorded data thus refuting one major aspect of astrology but at the same time establishing through their weather observations the foundations of modern meteorology. A second empirical programme was the recording of the biographies of famous people together with their horoscopes again to demonstrate correlation. Again the attempt failed but those collections, of which the most famous is Aubrey’s Brief Lives, are an invaluable source of data for historians. Going back over the whole history of astrology the astrological records of lunar and solar eclipses and other astronomical phenomena are also an invaluable data resource for modern astronomers. Call astrology rubbish and banish it out of existence and you banish an incredibly large part of the evolution of science.

This whole post was inspired by a commentator’s dismissal of the phlogiston theory. I’m not going to deliver a detailed analysis of the of the phlogiston research programme but it is by no means an exaggeration to say that the majority of the data and discoveries on which Lavoisier and his contemporaries constructed the foundations of modern chemistry were generated by chemists working within the phlogiston research programme.

Don’t reject failed and abandoned scientific research programmes but study and learn from them. If you are a working scientist there is a pretty good chance that the research programmes in which you do your own work will in their turn one day be abandoned but before they are they will also have generated a lot of very useful science.