The Rule of Three

Well, it has been a little while, as I have been busy, and so I will write something intricate and delicious for a change.

Our friends who "Love to Learn" have recently set up a web page just about Chesterton:

http://www.love2learn.net/literature/authors/authchesterton.html

At the top it has a very interesting quote:

How can it be a large career to tell other people's children about the Rule of Three, and a small career to tell one's own children about the universe?
[GKC, What's Wrong With the World CW4:118-9]

And I have seen this quoted elsewhere, often with a footnote wondering just what the Rule of Three is. So I loked it up, and started thinking about three.

What three are we talking about? What a great number! Well, we should not get all numerological, but we can start by considering the greatest paradox, and deepest secret ever known by human beings, where one name is stated to belong to three persons:

Go, therefore, and maqhteusate all nations, baptizing them in the name of the Father, and of the Son, and of the Holy Spirit.
[Mt 28:19]

Oh, I left that word in Greek on purpose. Let me write it in English letters, so you will see: mathêteusate which might be translated as "make disciples" or "make students" or "teach"... Yes, it has the same root as the word "mathematics" which means "the Learning" or "That Which is Studied". (Are you surprised? It's because mathematics is "studied" that St. Thomas Aquinas pointed out that math is the "easiest" of the sciences - yes, Barbie, math is easy! I will explore that topic in another post.)

Then we might consider this very strange and beautiful character of Hebrew and the other Semitic languages:

[Ancient] Egyptian shares the principal peculiarity of Semitic in that its word-stems consist of combinations of consonants, as a rule three in number, which are theoreticall at least unchangeable.
[Sir Alan Gardiner, Egyptian Grammar 2, emphasis added]

But that is not what is being referred to by GKC.

Next, going from the liberal arts side of the universe, ahem, I mean university, to the technical, we would find the famous Code unravelled by Watson and Crick, called the Genetic Code, wherein each three "bases" or nucleotides - the components of DNA - are translated into one amino acid, which is the component of protein. Here, in one of the great triumphs of true cooperation among different disciplines, from biology, chemistry and nuclear physics to electronics, photography, and material science (and yes, even computer science!) we are able to make visible and study the sequences of letters, actually standing for fragments of an incredibly complex chemical, and those sequences are interpreted as the various structures of the living being. Here is just a part of the code:

AAA Lysine
CCC Proline
GGG Glycine
UUU Phenylalanine

It is here, in cases such as sickle cell anemia, where we see that an error of just one single letter in the DNA causes an error of one single amino acid in a blood protein: the GAA or GAG for glutamate is written as a GUA or GUG translating to valine. You may have heard something like that before: "Not the smallest letter, not the smallest part of a letter, of the law shall pass away..." [See Mt 5:18]

But as interesting as that may be, neither is that what Chesterton meant.

So what DID he mean?

Well, I looked it up, and here is what I found:

rule of three: method of finding the number that bears the same ratio to one given number as exists between two other given numbers.
[The Concise Oxford Dictionary of Current English 1095]

So, if I want to know:

"Two is to What as five is to ten?"

or, if you can stand the crash of symbols:

"Find x where 2/x = 5/10"

So the rule of three is this:
"To find x in a/x = b/c, where a, b, c are given, calculate x as a*c/b."

Or, in our example, 2 times 10 divided by 5... so the answer is 4.

Frankly, it might be easier to tell a few about the universe. The fun thing is to try to do both at once.