Creationists And The Scriptural Value Of Pi

YET again, your Curmudgeon brings you the view from Answers in Genesis (AIG), one of the major sources of creationist wisdom. This time they have an article about an old but interesting question: Does the Bible make a mistake in claiming that pi equals 3?

In case you haven’t heard of this issue before, the bible (King James version) describes the construction of Solomon’s temple and a decorative pond in front of it. The relevant passages are:

And he made a molten sea, ten cubits from the one brim to the other: it was round all about, and his height was five cubits: and a line of thirty cubits did compass it round about. [1 Kings 7:23]

A circular pond, ten cubits in diameter but only 30 cubits around? That can’t be right. There’s another passage which will be referred to later:

And it was an hand breadth thick, and the brim thereof was wrought like the brim of a cup, with flowers of lilies: it contained two thousand baths. [1 Kings 7:26]

Let’s see what AIG has to say about the “problem of pi.” The bold font was added by us:

It has been alleged that the Bible is in error because it teaches that pi is equal to 3. Recall that pi is the ratio of circumference to diameter in a circle. [Skipping some obvious information about the value of pi.] So, is the Bible in error?

This is the sort of thing that disturbs creationists, who insist on a literal reading of scripture, thus rejecting much of modern science. They somehow manage to ignore (or re-interpret) scriptural passages suggesting that the earth is flat and that the sun orbits the earth, but let’s not confuse matters. We’ll stick with pi, which everyone knows isn’t 3, yet it’s one of those things about which creationists insist scripture cannot be wrong.

Let’s continue with the AIG article:

First of all, notice that this passage does not say “exactly ten cubits” or “exactly thirty cubits.” The numbers have been rounded to the nearest integer (or possibly the nearest multiple of ten). Dividing the circumference (30 cubits) by the diameter (10 cubits), we infer that pi is approximately equal to three. But, of course, pi is approximately equal to three, so the passage is quite correct.

At best, critics of the Bible could say that the Bible is imprecise here, but they cannot legitimately say that it is inaccurate or mistaken. Even scientists today will round off numbers at appropriate times. Remember that any decimal expression of pi must be rounded at some point anyway, since the expansion is infinite. There is no fallacy in rounding a number.

That’s not bad — it’s all just a question of precision. However, a problem remains. An argument can be made that the writers of this particular text were ignorant of pi, because it wasn’t even necessary to tell us the circumference of the pond. All they had to do was tell us the diameter, “10 cubits from the one brim to the other,” and the fact that “it was round all about,” which they did. If one knows about pi, then he would immediately know the circumference — roughly 31.4 cubits. The text must have been written by a scribe who didn’t know geometry. To him, it was no different than describing a rectangular room as being 10 cubits wide and 30 cubits long. Both dimensions are required — for a rectangle; but for a circular pond, the diameter alone is sufficient.

Moving along with the AIG article:

Second, we should consider the matter of significant figures. On a physics test, if a circle is said to have a diameter of 10 feet and the student is asked to compute the circumference, the correct answer is 30 feet — not 31 feet. The reason 31 feet is an incorrect answer is because it implies a precision that is unwarranted by the given information.

That’s really pathetic. Here’s more, and this is the “standard” creationist explanation:

Third, we should consider 1 Kings 7:26, which states that this cylindrical vessel “was a handbreadth thick.” Since the diameter is given from “brim to brim” (verse 23), the 10 cubits is referring to the outer diameter (which includes the handbreadth thickness of the rim). However, the circumference may well refer to the inner circle (as this is more representative of the pool of water inside the cylinder), which excludes the handbreadth.

That’s good. If the circumference wasn’t measured on the outside of the pond, then it would be less than 31.4 cubits, because the stated diameter of 10 cubits would then be decreased by two handhreadths. The given circumference of 30 cubits is much closer to what the Euclidean value should be for the smaller inside diameter’s circle. But then what of the earlier arguments about the “correctness” of 30 cubits as the outside circumference, due to a divine judgment about precision and significant digits? Which explanation gives us the true meaning of the text?

There is yet another problem here. For the thickness of the brim to be the saving detail, we must consider the difficulty of getting inside the pond and measuring the inner circumference of only 30 cubits. How does one extend a measuring rope around the inside wall of a circular water tank? Isn’t it simpler to run a rope around the outside? Well, one could climb inside the pond, before it contained water, place the measuring rope on the floor, and measure the inside circumference that way. But why would that be done, when the outside measurement is so much easier?

Further, why is the text so specific about the fact that the diameter was measured “brim to brim” but it fails to inform us that the circumference is being measured in a different way — inside the brims? At best, the text is sloppy. It can be salvaged with what seems to be a contrived explanation involving the width of the brim; but if that’s the proper reading, why would the text be written that way? It certainly seems an exceedingly clumsy way to describe the size of a pond.

Also, as with the outside circumference, we don’t need to be told the inner circumference. All we need to know is the diameter, and that the brim has the thickness of a handbreadth. Then we know the outside and inside diameter of the pond, and therefore both the outside and inside circumferences are known — but only if pi is known. The circumference is entirely superfluous. And embarrassingly troublesome.

This is a text that we’re told must be read word-for-word as literally true, yet to avoid an unacceptable value of pi — one that is clearly implied by the plain wording of the text — we are offered a collection of alternative readings. These proposed interpretations don’t agree with one another, yet one of them is required or else the bible says pi = 3. Well, which is it? Are we given the outside circumference of roughly 30 cubits, or are we given the inside circumference of exactly 30 cubits? With effort, the text can be read one way or the other. It can also be read plainly and directly, but then pi = 3.

Hey, the dimensions of the temple pond were so important that they appear in scripture twice! This too is from the King James Version:

Also he made a molten sea of ten cubits from brim to brim, round in compass, and five cubits the height thereof; and a line of thirty cubits did compass it round about. [2 Chronicles 4:2]

Make of that what you will. Here’s the end of the AIG article:

In conclusion, the accusation that the Bible has made a mathematical mistake is totally without merit. The biblical answer is spot on, given the information presented and the precision of the numbers in question.

Maybe so. Such trivia are entirely unimportant to us. A few poetic or metaphorical passages about the heavens, and even a math error or two, are insignificant in a book that was never intended to be a flawless science or math text. But those who adopt rules like AIG’s Statement of Faith are compelled to struggle with difficulties of their own making. AIG’s statement is typical of many such. It says:

The Bible is divinely inspired and inerrant throughout. Its assertions are factually true in all the original autographs. It is the supreme authority in everything it teaches. Its authority is not limited to spiritual, religious or redemptive themes but includes its assertions in such fields as history and science.

But while AIG is laboring so mightily over their self-created and what we see as utterly unessential mathematical difficulties, we have another question:

If creationists can manipulate the text to the extent that they do in order to preserve the illusion that scripture is accurate about the value of pi — when it obviously isn’t — why can’t they employ the same skill to understanding the six days of creation, and thereby harmonize Genesis with modern science? They could thus be spared all the mind-destroying nonsense they force upon themselves to oppose the theory of evolution and so much else that science teaches us.

Copyright © 2009. The Sensuous Curmudgeon. All rights reserved.

• • • • • • • • • • •

. . Permalink for this article