A famous quotation from a famous source this week, but one which is probably famous for the wrong reasons. First, the famous version:
The good Christian should beware the mathematician and all those who make empty prophecies. The danger already exists that the mathematicians have made a covenant with the devil to darken the spirit and to confine man in the bonds of hell.
St Augustine, De Genesi ad Litteram II, xvii, 37 (translation as quoted by Morris Kline in Mathematics in Western Culture, 1953).
Wow… mathematicians as death metal musicians! I admit I’ve met a few people who think of maths like that, but I’m not sure it’s because of their religious views… So what’s going on here?
The first point, of course, is that Augustine wasn’t writing in English. What he actually wrote, in Latin, was:
Quapropter bono christiano, sive mathematici, sive quilibet impie divinantium, maxime dicentes vera, cavendi sunt, ne consortio daemoniorum animam deceptam, pacto quodam societatis irretiant.
In case this isn’t immediately clear (surely not?), an alternative translation by one J. H. Taylor might help:
Hence, a devout Christian must avoid astrologers and all impious soothsayers, especially when they tell the truth, for fear of leading his soul into error by consorting with demons and entangling himself with the bonds of such association.
A bit more comprehensible maybe — but what’s happened to those devilish mathematici in the original? The point is that the word “mathematics” has a complicated history. The Greek root means, roughly, “learning”, and for millennia the branches of learning we now regard as mathematics and as astrology were closely intertwined. A major use of maths was to predict astronomical events and cast “accurate” horoscopes, and the word “mathematician” was being used in the sense of “astrologer” as late as the 1700s: the OED quotes Lord Shaftesbury, in 1711, grumbling that “Astrologers, Horoscopers, and other such are pleas’d to honour themselves with the Title of Mathematicians.” (By the way, it’s not just in English that the distinctions are blurred: when Don Quixote is thrown off his horse, an algebrista or algebraist is summoned to treat him. In the 1600s, medicine involved a lot of astrology, and hence a lot of mathematics too.)
The irony is that great deal of good mathematics came out of what we now recognise as a lousy science. I’ll leave it to you to imagine modern parallels…