The tools used by astrologers appear daunting to the uninitiated – all those tables with weird symbols all over the place, the intricate calculations, the dazzling horoscopes with all their esoteric paraphernalia; this surely is science at work.
In some ways, it is. Ephemeris data have been lifted from NASA databanks. Spheroidal geometry underpins the Tables of Houses. The stuff of science is certainly there. Indeed there was a time when astrology provided an overarching conceptual framework for much of what was then science. Chaucer tells us that the 14th century physician ‘kept his patients from the pall through horoscopes and magick natural’ (modernised paraphrase). So what changed?
It was not so much advancing technology or momentous discoveries that brought about modern science but the ‘intellectual technology’ that came to be applied to observations and measurements from the late 17th century on. The scientific mindset is empirical – it applies the axiom that knowledge comes about through observation rather than through intuition or reliance on authoritative pronouncements.
A relevant aside is that the emergence of Deism was a great boost for empirical reasoning. Deism arose in the late 17th century and was an intellectual norm throughout the 18th century and well into the second half of the19th, especially in England. Deism held that a supernatural being had created the universe and the ‘laws’ that make it function but had then stepped back and allowed the system to work according to those rules without further intervention. People like Newton were now free to look for purely material mechanisms for natural phenomena without invoking any supernatural elements, which after all are not amenable to empirical testing.
Reliance on the empirical approach to reality brings with it the need to change one’s conceptual models when new data indicate that the old model no longer works well. Some ill-informed people mock science for constantly ‘changing its mind’. But that is simply the intellectual honesty of science in operation: we have new data that doesn’t fit in well with our theoretical framework so we modify the theory or even jettison it – the history of science is strewn with the carcasses of abandoned ideas that may once have held great sway, such as Phlogiston, the Steady State Universe, and the Four Humours model of disease.
Science is a method rather than a set of beliefs, and it is most unwise to present science as the second of these. To say ‘scientists believe X, therefore X is true’ is not the way scientific reasoning works. It is an appeal to authority on a par with saying that some ‘holy’ book claims something which is therefore true. And it completely ignores the issue that is at the core of the matter: why scientists hold something to be true.
Astrology fails the test of being a science because its central paradigms are not derived from empirical observations. The fundamental axiom ‘As above, so below’ is not an empirically testable claim; it is a philosophical dictum. Attributing certain characteristics to people born under a certain zodiacal sign is not based on exhaustive sampling and psychometric testing. Now of course some people will comply very well with those profiles generated from astrology – yours truly, for instance, is a textbook case of Sagittarius with a good measure of Cancer thrown in. But this is so-called ‘confirmation bias’: it fits so we’ll use it as evidence, but if it doesn’t fit we’ll ignore it or use Kepler’s ultimate cop-out of ‘The stars incline, they do not compel’. Astrological claims thereby become unfalsifiable, and as the late great philosopher of science Karl Popper eruditely pointed out, a claim must be [empirically] falsifiable for it to qualify as a scientific one.
Is History a science? No, it isn’t. It occasionally makes use of scientific tools, such as chemical analysis and radiometric dating, but it can’t operate as a science because there are too many gaps in its primary data set requiring plugging by inference. There is no replicability and falsifiability is a tenuous paradigm to apply to many historical claims. Does that mean History is not valid ‘knowledge’? Of course it doesn’t. It’s just that it has to abide by different rules of evidence from chemistry or geology.
It struck me that many commentators in the row over the inclusion of Māori ethnoscience  in science curricula – some of whom ought to know better – have been conflating ‘knowledge’ and ‘science’. History is knowledge but not science, astrology is knowledge but not science. ‘Knowledge’ here refers to what in German is called a wissenschaft – a body of systematic knowledge. Every wissenschaft operates according to its set of rules, and these are generally non-transferable. You don’t apply the Periodic Table or Newton’s Laws to the study of History. This does not demean the disciple of History; it means that the tools are not appropriate to the job any more than a wood rasp is useful to a motor mechanic without demeaning either carpentry or motor mechanics.
Are wissenschafts ‘equal’? This is a rather silly question, akin to asking whether carpentry and motor mechanics are ‘equal’. Each wissenschaft has its own domain with tailor-made rules.
One of the things we supposedly do in schools is expose young minds to different ways of thinking. You do not do so by saying that scientists believe X and historians believe Y but by inducting learners into the mindsets and associated rules of evidence and patterns of reasoning that scientists and historians abide by. Pitting them against one another is as naïve as it is pointless.
Astrology is a wissenschaft that school students should be exposed to, but not as a rival to astronomy or psychology. So is the traditional Māori conception of reality. But not in the Science classroom any more than folklore should be taught as History.
 Readers may find my earlier article ‘Science, pseudoscience and ethnoscience’, Breaking Views 12 September 2020 HERE, useful. There is admittedly some overlap between that article and this one. At the time, it went virtually unnoticed, owing to my horoscope having got it wrong about when this would become a major public issue. Oh well, it was only a few months out……….
Barend Vlaardingerbroek BA BSc BEdSt PGDipLaws MAppSc PhD is a retired academic who spent many years at universities in PNG, Botswana and Lebanon and is now in Turkey awaiting a vacant slot in the MIQ system and wondering whether he will die of old age first. Feedback welcome at firstname.lastname@example.org.