Why Accept the Pythagorean Theorem?

Article ID: JAE393 | By: Paul A. Nelson
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Pythagorean Theorem

This article first appeared in the Effective Evangelism column of the CHRISTIAN RESEARCH JOURNAL, volume 39, number 03 (2016). The full text of this article in PDF format can be obtained by clicking here. For further information or to subscribe to the CHRISTIAN RESEARCH JOURNAL go to: http://www.equip.org/christian-research-journal/

Suppose I said that you knew the Pythagorean theorem (A2 + B2 = C2) because you were educated in the United States, where students routinely study geometry. “You’re right, Paul,” you would probably reply, wondering if we could perhaps find something more interesting to discuss.

But then I add that because you had to learn the Pythagorean theorem, you have no good reason to believe the theorem is true. You were taught it as a matter of standard educational practice, leaving you no choice but to memorize it. Anything soaked up from one’s culture in that fashion, however, should be doubted.

Now you’re puzzled. The Pythagorean theorem follows deductively from the axioms of Euclidean geometry, you point out, but how or when one learns those axioms is irrelevant to the truth of the theorems derived from them. A2 + B2 = C2 is true as a proposition of geometry, whether one memorized it in a math classroom, or proved it thousands of years earlier on a sunny afternoon in ancient Alexandria.

Logicians have a name for your argument, you tell me. They call it the genetic fallacy. Such arguments are fallacious because they confuse the causal origin of one’s beliefs (their genesis) with the entirely independent question of whether those beliefs are true.

In his writings and public lectures, Richard Dawkins—formerly a professor at Oxford University, but now a full-time promoter of atheism—presents an argument about religious belief that possesses a superficial plausibility. The plausibility arises from facts about the transmission of human culture. A child growing up in Boston, for instance, is more likely to be a Red Sox fan than he is to be a Yankees fan, simply as a matter of familiarity. Likewise, a child raised by Christian parents is more likely to become a Christian herself than a child raised by Islamic, Hindu, or secular parents, and for the same reason: familiarity.

Here’s how Dawkins puts it in the opening of his bestselling book The God Delusion:

If you feel trapped in the religion of your upbringing, it would be worth asking yourself how this came about. The answer is usually some form of childhood indoctrination. If you are religious at all, it is overwhelmingly probable that your religion is that of your parents. If you were born in Arkansas and you think Christianity is true and Islam false, knowing full well that you would think the opposite if you had been born in Afghanistan, you are the victim of childhood indoctrination.1

Later Dawkins devotes an entire chapter, “Childhood, Abuse and the Escape from Religion,” to the question. Teaching any child about any religion, he argues, without simultaneously enabling that child to dissent, represents child abuse. “Our society,” he writes, “including the non-religious sector, has accepted the preposterous idea that it is normal and right to indoctrinate tiny children in the religion of their parents.”2 This is preposterous, Dawkins contends, because the child cannot decide for himself.

That child believes a falsehood, Dawkins concludes, because the falsehood was taught to the child before he could resist it.

Don’t Pity the Kids. Dawkins’s argument draws plausibility from the fact that humans are more likely to absorb what surrounds them as they develop, from infancy to adulthood, than they are ideas to which they have never been exposed.

But, from this rather humdrum statistical fact, what follows about the truth of those ideas? After all, Dawkins doesn’t object to children learning arithmetic. We teach arithmetic to children because arithmetic is true and useful, and the best time to learn true and useful things is when one is young. That’s the first clue to the enormous error at the heart of Dawkins’s argument.

It’s not that children are taught the religion of their parents that troubles Dawkins. Unless he proposes to raise children in a total cultural vacuum (which truly would be child abuse), Dawkins would admit that children must be taught something about the world. He wants them to be taught what is true. Dawkins thinks the world’s major religions are false. Therefore children should not be given religious instruction, for the same reason that we do not teach them that A2 + B2 = C3.

In short, Dawkins objects to “childhood indoctrination” not because children are involved but because—as he sees it—falsehoods are taught to them. But Dawkins would still object if those falsehoods were taught only to adults. Falsehood brings its own condemnation, as does truth its own reward.

We could stop here, and toss Dawkins’s “childhood indoctrination” argument into the genetic fallacy rubbish bin. Yet a closer examination of Dawkins’s argument reveals so many layers of confusion, error, and self-referential incoherence that we can take away a cautionary tale from the mess.

Keep a Mirror Handy, Sir. Richard Dawkins proudly proclaims his atheism. Yet Dawkins was also raised as an Anglican Christian, and indeed, until the age of sixteen, believed in a Creator who intelligently designed organisms. As he recounts in his autobiography, An Appetite for Wonder, even after abandoning the doctrinal specifics of Anglicanism, he says, “I retained a strong belief in some sort of unspecified creator, almost entirely because I was impressed by the beauty and apparent design of the living world, and—like so many others—I bamboozled myself into believing that the appearance of design demanded a designer….I was a strong believer in a non-denominational creator god.”3 So what happened? Dawkins himself explains the shift:

I became increasingly aware that Darwinian evolution was a powerfully available alternative to my creator god as an explanation of the beauty and apparent design of life…I went through a period of doubting the power of natural selection to do the job required of it. But eventually a friend…persuaded me of the full force of Darwin’s brilliant idea and I shed the last vestige of theistic credulity, probably at the age of about sixteen. It wasn’t long then before I became strongly and militantly atheistic.4

What happened was that Dawkins changed his mind. Darwinian theory replaced what previously convinced Dawkins of intelligent design. Given his assertions about the power of “childhood indoctrination,” however, that change of mind should have been all but impossible—unless being taught religion as a child does not entail that one will believe that religion as an adult. If Dawkins could jettison his Anglicanism, then “childhood indoctrination” does not have the permanence he claims.

Charles Darwin also changed his mind as an adult. In the Introduction of the Origin of Species, he explains that—as an adult naturalist, formerly persuaded of divine creation—he changed his opinion: “I can entertain no doubt, after the most deliberate study and dispassionate judgment of which I am capable, that the view which most naturalists entertain, and which I formerly entertained—namely, that each species has been independently created—is erroneous.”5

Mirabile dictu6—someone else overcame his upbringing.

No atheist who argues for the permanence of religious instruction should be allowed to make such an argument without at least glancing in a mirror. Interestingly, the reverse scenario can also be observed. Biologist and intelligent design theorist Dean Kenyon and the creationist geneticist John Sanford both entered their careers as scientists fully persuaded of Darwinian evolution. But people change their minds. It’s what rational beings do.

The Peril of Taking Memes Seriously. Anyone puzzled by the self-referential incoherence of Dawkins’s “childhood indoctrination” argument should look for clues to its irrational power elsewhere in The God Delusion. The best place to go digging might be Chapter 5, “The Roots of Religion,” where Dawkins lays out his case for religion as a meme.

Memes—a word Dawkins coined in 1976, with explicit parallels to “gene”7—are self-replicating cultural entities such as musical jingles or slang, which move autonomously from brain to brain through human populations, like viruses infecting cells. Successful memes may propagate themselves despite being false or downright harmful. The details of memetic theory need not concern us here.8 I’m more interested in the underlying philosophy, which downplays human agency and freedom. In other words, I want to analyze the materialism motivating Dawkins’s argument at its deepest level. Why say religion is a meme?

Dawkins downgrades human reason and free choice because a freely acting or choosing agent may not be (entirely) subject to physical law. Such an agent may not be wholly a material system, and thus may judge the truth or falsehood of a proposition not because he was controlled by memes that captured and parasitized the circuitry of his brain but by asking if that proposition fits with reality as he perceives it.

Memes relieve one of that task of mature judgment. They turn active minds into passive meat machines, and if a mind is only a biological brain that can be parasitized by memes invading from elsewhere, then those helpless machines should be protected from pernicious memes such as “God exists” or “You will survive your own death.” No wonder Dawkins is so agitated by children learning about religion. Their brains represent tabulae rasae (“blank slates”) just waiting to be captured by bad memes, transmitted without choice by other infected brains. Meme zombies threaten, out to the horizon.

We can take another perspective, of course. Maybe the reason that the idea “You will survive your own death” (which Dawkins places at the top of his list of religion memes9) so pervades world religions is because the idea is true. Saying that personal immortality might be true, however, means that we must weigh carefully what counts as evidence for its truth. We can’t offload the task onto a meme and surrender our thinking to its active control.

We have to be grown-ups, and think.

And, in the end, I’m sure that’s what Richard Dawkins would want: thinking, rational beings, weighing the evidence for themselves. —Paul A. Nelson


Paul A. Nelson (PhD, evolutionary theory and philosophy of science, University of Chicago) has been a Fellow of the Discovery Institute since 2004. He is also adjunct professor in the Master of Arts program in science and religion at Biola University.


  1. Richard Dawkins, The God Delusion (New York: Houghton Mifflin, 2006), 3.
  2. Ibid., 339.
  3. Richard Dawkins, An Appetite for Wonder: The Making of a Scientist (New York: Harper-Collins, 2013), 140–41.
  4. Ibid., 142.
  5. Charles Darwin, Introduction, On the Origin of Species (Cambridge, MA: Harvard University Press, 1964), 6.
  6. Literally, “wonderful to say.”
  7. Richard Dawkins, The Selfish Gene (Oxford: Oxford University Press, 1976).
  8. Consult Susan Blackmore, The Meme Machine (Oxford: Oxford University Press, 1999).
  9. Dawkins, The God Delusion, 199.