On the first page of Mathematics for the Nonmathematician, mathematician Morris Kline quotes Augustine of Hippo as saying:

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.

Later in the same work, he says that "despite St. Augustine, the reader is invited to tempt hell and damnation by engaging in the study of the subject."

Is this quote genuine? If so, in which work can it be found and is it a reasonable interpretation of the text?

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    He condemned numerology and similar superstitions. Remember, that the word "mathematician" as we use today didn't carry the same thing more than a thousand years ago. Note the word "prophecy" in the text! – vsz Aug 1 '16 at 4:10
  • @vsz Considering certain theological outlooks on fields of math and science today, I'd say the word "prophecy" is still in some use with regard the subject, however ironic or hypocritical. – TylerH Aug 1 '16 at 15:05

You ask whether it's a reasonable interpretation of the text.

Book IV of Augustine's Confessions (in Latin), which was cited in this answer, includes:

Itaque illos planos, quos mathematicos vocant, plane consulere non desistebam, quod quasi nullum eis esset sacrificium, et nullae preces ad aliquem spiritum ob divinationem dirigerentur.

So the text includes the word mathematicus (-cos).

Looking at the definition of this word according to Lewis and Short it means,

A. Măthēmătĭcus , i, m.
1. A mathematician, Cic. de Or 1, 3, 10; id. Ac. 2, 36, 116; id. Tusc. 1, 2, 5; Sen. Ep. 88, 26.—
2. An astrologer (post-Aug.): “mathematici, genus hominum potentibus infidum, sperantibus fallax, quod in civitate nostra et vetabitur semper et retinebitur,” Tac. H. 1, 22: “nota mathematicis genesis tua,” Juv. 14, 248; Tert. Apol. 43: “qui de salute principis ... mathematicos consulit, cum eo qui responderit, capite punitur,” Paul. Sent. 5, 21, 3.—

So I think that dictionary is saying that in "post-Aug." times the word is used for "an astrologer".

The same sentence (of Augustine) includes the word divinationem which Lewis and Short defines as,

dīvīnātĭo , ōnis, f. divino.
I. The faculty of foreseeing, predicting, divination, μαντική (cf.: “augurium, auspicium, vaticinium, praesagium, praedictio),” Cic. Div. 1, 1; 2, 5, 13; 2, 63, 130; id. N. D. 1, 22, 55; id. Leg. 2, 13, 32; id. Rosc. Am. 34, 96; Nep. Att. 9, 1; 16 fin.: “animi,” Cic. Fam. 3, 13: “mendax,” Vulg. Ezech. 13, 7.—

So that (context, including also the context of the previous sentences) supports the "astrology" sense of the term.

So instead of "beware the mathematician and all those who make empty prophecies", a more faithful translation might be, "beware the astrologer" (and presumably other people who practice augury).

My personal guess is that the practice of astrology might have looked like a branch of what we know as mathematics: including e.g. geometry to divide the zodiac into houses or whatever.

Looking at the (ancient) Greek the word derives from a root meaning "learning", so it means like "fond of learning", and can be used to mean "scientific" (especially "mathematical"); "astronomical"; and/or "astrological".

Can you find an expert confirmation that your interpretation is correct? Do historians or philosopher agree with your (somewhat arbitrary) choice of meaning?

Yes, for example this translation with footnotes talks about astrology w.r.t. that passage, e.g.:

Astrology recurs pastorally throughout Augustine's career. The same vocabulary, and the same scriptural quotations, appear over and over. The place of astrology in African life etc.

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    "Sounds weird. But keep in mind that (up until) the Renaissance the words astrologus, astronomus and mathematicus are synonymous." Mainly because, before Newton gave us physics and the Industrial Revolution gave us modern engineering, mapping the stars was one of the only practical uses that existed for mathematics. – Mason Wheeler Jul 30 '16 at 17:08
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    @MasonWheeler There must be many of those (conflated professions): e.g. engineer/sapper; chemist/alchemist; barber/surgeon; scribe/monk; smith/farrier; philosopher/naturalist; geometer/surveyor; ... – ChrisW Jul 30 '16 at 17:21
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    @ChrisW you are basically saying that Augustine meant "astrologer" when he said "matematician". Showing a dictionary entry with two meanings shows it's possible but does not prove it. Surely the people that translated the text to English were aware of the possibility but decided to use "matematician" for a reason? – Sklivvz Jul 30 '16 at 23:16
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    @Sklivvz I appended to the answer to reference a different translator for you. He didn't say "mathematician": he wrote a similar-sounding Latin word. – ChrisW Jul 30 '16 at 23:18
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    Thanks, I also found more confirmation, added in a separate answer. – Sklivvz Jul 31 '16 at 0:51

See Book IV of Augustine's Confessions (Project Gutenberg link). This translation is credited to E. B. Pusey.

I remember also, that when I had settled to enter the lists for a theatrical prize, some wizard asked me what I would give him to win; but I, detesting and abhorring such foul mysteries, answered, "Though the garland were of imperishable gold, I would not suffer a fly to be killed to gain me it." For he was to kill some living creatures in his sacrifices, and by those honours to invite the devils to favour me. But this ill also I rejected, not out of a pure love for Thee, O God of my heart; for I knew not how to love Thee, who knew not how to conceive aught beyond a material brightness. And doth not a soul, sighing after such fictions, commit fornication against Thee, trust in things unreal, and feed the wind? Still I would not forsooth have sacrifices offered to devils for me, to whom I was sacrificing myself by that superstition. For what else is it to feed the wind, but to feed them, that is by going astray to become their pleasure and derision?

Those impostors then, whom they style Mathematicians, I consulted without scruple; because they seemed to use no sacrifice, nor to pray to any spirit for their divinations: which art, however, Christian and true piety consistently rejects and condemns. [...]

The last sentence seems to capture the spirit of the quote you gave. The preceding paragraph makes it clear that he is talking about some sort of soothsayer or astrologer who is able to predict the future, although (in contrast to the aforementioned "wizard") without making sacrifices to devils.

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    That last sentence seems to describe statisticians (and meteorologists and astronomers and geologists etc.). – slebetman Jul 30 '16 at 4:35
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    But he's saying he happily consults mathematicians, because they don't consort with devils. – OrangeDog Jul 30 '16 at 17:29
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    @OrangeDog: Note the past tense "consulted". The larger context (earlier in Book IV) makes clear that he's describing a sinful period of his life, from which he has since reformed. And the end of the sentence is saying that although he thought at the time it was okay to consult mathematicians, being a lesser evil than wizards, in fact Christians and the pious should "reject and condemn" this practice. – Nate Eldredge Jul 30 '16 at 18:32
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    Ah, "which art" refers to the divinations, rather than the sacrifice and prayers. – OrangeDog Jul 30 '16 at 20:52
  • The phrase "whom they style Mathematicians" would seem to suggest that he recognized the difference between astrology/superstition and mathematics, and was warning about the difference. – wedstrom Aug 1 '16 at 15:31

I'll add some more evidence to the other answers, here's what I found.

From a scholarly point of view, there seem little doubt that he meant astrologers, who at the time were called mathematici or genethliaci: this is clearly seen in a different book by Augustine, De Doctrina Christiana. Here's an extract from the English version available from the site of Georgetown university.


  1. Nor can we exclude from this kind of superstition those who were called genethliaci, on account of their attention to birthdays, but are now commonly called mathematici.

I found this link through a nice, evidence-based piece on exactly the claim in question written by P. Odifreddi (a skeptic but also a... mathematician) here (in Italian).

  • Hey, your Italian paper identifies a different and more accurate quote: not the sentence in Book IV quoted in Nate's answer which is merely a similar topic, but the actual quote from the OP. – ChrisW Jul 31 '16 at 1:00
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    Also, LOL at the phrase "Si tratta, dunque, di un banale errore di traduzione" -- so cool about it. – ChrisW Jul 31 '16 at 1:03
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    Also, OMG at "le cui conseguenze sono state devastanti per la Chiesa, autorizzando una interpretazione oscurantista dei suoi orientamenti e scopi."! He's saying that the Church mistranslated it and took the mistranslation seriously, with "devastating consequences"? Plot twist! So the Church says (or said) that St. Augustine was anti-mathematics? – ChrisW Jul 31 '16 at 1:06
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    @ChrisW nope, that passage merely means that the consequences of the mistranslation were devastating for the Church, because the passage was used to support accusations of obscurantism. – Sklivvz Jul 31 '16 at 1:29
  • It might be good to add a reference to (and quote from) "exactly the claim in question" now that you found it: Latin and English. – ChrisW Jul 31 '16 at 13:36

I would regard Kiline's translation as a distortion; Augustine was not criticising the methods but the evil sources of predictions.

It might be worth looking at the original quote from Augustine, which was in De Genesi ad Litteram libri duodecim (Twelve Books on the Literal Meaning of Genesis) Book 2, 17:37

Aliquando autem iidem nefandi spiritus etiam quae ipsi facturi sunt, velut divinando praedicunt. Quapropter bono christiano, sive mathematici, sive quilibet impie divinantium, maxime dicentes vera, cavendi sunt, ne consortio daemoniorum animam deceptam, pacto quodam societatis irretiant.

which might be translated as

However, sometimes even those that are made of the same evil spirits divine the truth. Therefore a good Christian should beware not only of mathematicians/numerologists/astrologers but also of all impious diviners, especially those who tell the truth, as otherwise they might deceive the soul, enmeshing it in a partnership agreement with demons.

So this is a warning against all those predicting the future without the aid of God, whether they use mathematics or not, and in particular warning against those who make accurate predictions.

  • This might be a better answer without "whether they use mathematics or not" in the last sentence. And better (e.g. according to @Sklivvz) to select and quote an expert translation. – ChrisW Jul 31 '16 at 14:18
  • @ChrisW: My final comment is how I read it: I do not see this as an attack on mathematicians as such. You are welcome to look for an expert translation (apparently there is one by John H Taylor in 1982), or you could look at the original Latin yourself (there are enough tools on the internet to parse and translate this) if you doubt my attempt based on what I learnt 40 years ago – Henry Jul 31 '16 at 15:27
  • If you can read Italian, Wikiquote gives precisely this phrase as an example of a misquotation – Henry Jul 31 '16 at 21:44
  • Thanks. The same quote is is the paper referenced in Sklivvz's answer. – ChrisW Jul 31 '16 at 21:50
  • Indeed, through Wikiquote gives what it thinks is a better translation «Ecco perché un buon cristiano deve guardarsi non solo dagli astrologhi ma anche da qualsiasi indovino che usi mezzi contrari alla religione, soprattutto quando dicono il vero, per evitare che ingannino l'anima mettendola in rapporto con i demoni e la irretiscano in una specie di patto d'alleanza con loro.» which I think is close to my "not only..but also..." and "especially those who tell the truth" (though strictly speaking the Italian says "above all when they tell the truth"), confirming Kline's distortion – Henry Jul 31 '16 at 22:03

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