With Love from North Africa: St. Augustine on Math and the Existence of God

You like math?  Or, if your're from certain parts of the world: You like the maths?  Oh, don't turn away.

St. Augustine (354-430) has an argument for the existence of God based on the reality of number, of 

mathematical law.  Here it is in summary form below in 11 points.  Of utmost importance is the first 

premise, which states that God, as the Highest Being or Good, is greater than the human mind, and 

whatever is greater than the human mind would be the highest good.  Maybe you think the universe 

itself is greater than the human mind.  You'd be wrong, of course.  The universe doesn't contemplate the 

meaning of itself.  In this argument, the intellectual giant from modern day Algeria is having a 

conversation with his friend, Evodius.  Augustine already knows that people know God exists by the 

mere observation of nature, as it says in Psalm 19:1-6 and Romans 1:18-20.  But, just in case people 

need rational argument, Augustine is ready with the whip to snap people to attention of things greater 

than the human mind: wisdom and the laws of mathematics.  These, in turn, speak of Truth, and the 

Truth is the greatest good.  God is also the greatest good, and the embodiment of Truth in the person of 

Jesus Christ.  Here it is.  I wrote a paper on this subject, replete with Latin footnotes!  Doesn't that make 

me special?  I'll spare all that, and just let you contemplate the argument.  If you want a copy of the 

paper, just email me.  It's not been graded yet, so I can't say it's worth the read.  Augustine is 

worth reading though, and here is a summary of his argument in his discourse with Evodius in The Free 

Choice of the Will, Book II.  Pay special attention to point number 7.  

1)   “You (Evodius) granted that if I could prove that there was something above our minds, you would admit this is God, provided that there was still nothing higher.”[1]

2.    Augustine systematizes the natural order into three categories: a) things that exist, b) things that exist and live, and things that exist, live, and also understand. 

3)      The act of understanding is “most excellent”[2] among things that exist and live.

  

4)      Sense-perception (or, the five senses) exist in the human being, and in animals.

5)      Animals, as well as humans, share an “inner sense,” which we might call “instinct.”  (Instinct is that sense which enables an animal to “seek and acquire things that delight and to repel and avoid things that are obnoxious.”)[3]

6)      Reason exists in man only.  The “inner sense” of 4) is the servant of reason in the human knower.

7)   Numbers (or, mathematical laws), differentiated from corporeal bodies i.e. food and water, are infinite, unchanging, eternal truths.  Reason shows these things to exist.  For example, take any integer, n, and double it.  The distance between n and its double and n zero is the same, ad infinitum.  We know this to be true, of course, even though we cannot observe all numbers.  Therefore, this mathematical law, or "rule of the double" exists outside the human mind, for it is neither dependent upon the mind in order to be observed and named (nominalism), nor is it created by the human mind (conceptualism), for this would lead to epistemological relativism, which is self-refuting.  These things are real, ya'll (realism).  

8)      Number and Wisdom are identical (or, number is “contained” in wisdom).  And yet, even if they are not identical, or, if it cannot be shown that the former is contained in the latter or vice versa, it is certain that both number and wisdom are true and unchangeably true (immutable).  These truths are discovered, not invented, for if the latter, they would change with the human mind, which changes.

9)      These truths come from one Truth itself, which is higher than reason. Truth is the highest conceivable concept.

10)  This truth, as the highest good and most excellent thing, is God Himself, per the first premise. 

11)  Therefore, God exists, by reductio ad absurdum. It is absurd to believe that Truth does not exist, and it is impossible that anything is higher than Truth, which, according to the first premise, is God.[4]

Now, the greatest part of the argument that needs teasing out is the conflation of "many truths" found in 

mathematical laws and wisdom, with One Truth, from which all truths come.  A metaphysical system 

similar to the Aristotelian/Thomistic paradigm that deems Truth as Being would do the trick.  Or, a 

Principle of Sufficient Reason as a Cause of truth from which all truths come would do that as well.  The 

next time you look up at the stars or contemplate the rule of mathematical law, think on this argument, 

and the great wisdom in the Mind of God.

Cheers,

Chris 

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[1] Andrew B. Schoedinger, Reading in Medieval Philosophy, (Oxford: Oxford University Press, 1996), p.22.

[2] Ibid., p.6.

[3] Ibid., p. 7.

[4] Douglas Groothuis argues similarly for the ontological argument in Christian Apologetics, (Downers Grove, Ill: Intervarsity Press, IVP Academic, 2011), p.188.