Reasons to Believe

Does Ockham's Razor Support Naturalism?

William of Ockham (c. 1285-1349), a Franciscan monk and philosopher,1 is remembered for his principle of parsimony or simplicity, popularly called “Ockham’s Razor.” He stated that “Entities are not to be multiplied without necessity,” and “What can be done with fewer [assumptions] is done in vain with more.” In other words, when confronted with two seemingly equal explanatory hypotheses, the simplest or most economical explanation should be granted logical deference.

Some atheists assert that application of Ockham’s Razor makes atheism and its accompanying worldview of naturalism a more reasonable alternative than Christian theism. They argue that atheism is to be preferred over theism because atheism posits at least one less entity (no God) in the inventory of ultimate reality than does theism. Atheists generally believe that their naturalistic, materialistic worldview can explain reality, truth, meaning, value, morality, beauty, and reason in one world, whereas Christian theism requires two worlds (both the physical and transcendent realms of reality).

Yet Ockham’s Razor, while meaningful in evaluating competing explanatory hypotheses of ultimate reality, cannot stand alone as the principal or final test of what is reasonable or truthful.2 The simplest explanation may deserve initial deference over the complex explanation, but sometimes what appears to be the simplest theory may actually be simplistically inadequate. In that case the more complex view becomes logically necessary. I suggest that Ockham’s Razor addresses only half of the necessary explanatory equation. The fuller logical perspective comes in what I stipulatively call the “mean test.”  This test asserts that the worldview balanced between complexity and simplicity is a better barometer of ultimate truth and reason. Accordingly, an acceptable worldview (an interpretation of reality) will be neither too simple (the reductionistic fallacy) nor unnecessarily too complex (Ockham’s Razor). The test states that the simplest, most economical, and yet fully orbed worldview is best (explanatorily superior). The mean test strives to guard against both superfluous and simplistically inadequate explanations of reality.3

Christians identify two weaknesses in naturalism when the mean test is applied. First, while naturalism may be in one sense simpler than its rival theism (by denying the existence of the transcendent world), naturalism is itself a metaphysical system, and not merely reducible to the scientific enterprise. In the end it doesn’t appear to be all that simple or precise. The idea that complex reality (the world, life, consciousness, etc.) can be reduced to or explained solely by the natural world seems a difficult and presumptuous claim. I remain unconvinced that naturalism is truly a simpler or more economical explanation of reality than is Christian theism.

Second, naturalism holds that such meaningful realities as life, the mind, personhood, and reason came from an accidental natural mechanism (e.g., phylogenetic evolution). But any such mechanism would lack these realities. The effect appears to be profoundly greater than the cause. How does this inconceivably improbable cause-effect anomaly square with the foundational scientific principle of causality? How can such rational and objective enterprises as logic, mathematics, and science be the result of an unguided, accidental, purely mindless natural process?

The mean test strikes me as a more balanced and reasonable calibrator of worldview truth-claims, and naturalism doesn’t score any higher on this test than does Christian theism. In fact, Christian theism’s robust explanatory power and scope (including helping human beings understand life and its challenges) may be one of its most probative features. The meaningful realities of life (the world, abstract entities, consciousness, morality, logic, etc.) need an adequate metaphysical ground. The God of the Bible stands not as a “god of the gaps” superstitious substitute for ignorance, but rather as a simple, economical, and yet fully orbed explanatory hypothesis for the various meaningful realities discovered in the world and in human life.


  1. For a detailed discussion of William of Ockham’s philosophical and theological views, see Frederick Copleston, A History of Philosophy, vol. 3 (New York: Doubleday, 1993), 43-152; and Paul Edwards ed., The Encyclopedia of Philosophy, vols. 7 and 8 (New York: Macmillan, 1967), s.v. “William of Ockham.”
  2. I summarize nine suggested worldview tests in Hugh Ross, Kenneth Samples, and Mark Clark, Lights in the Sky &Little Green Men (Colorado Springs: CO, Navpress, 2002), 156-58.
  3. A thoughtful and fair-minded comparison of the worldviews of naturalism and theism is provided in William J. Wainright, Philosophy of Religion (Belmont, CA: Wadsworth, 1988), 166-75. Wainwright’s thinking has in some respects influenced my own on this topic.

Subjects: Logic, Naturalism

Kenneth R. Samples

I believe deeply that “all truth is God’s truth.” As an RTB scholar I have a great passion to help people understand and see the truth and relevance of Christianity’s truth-claims. Read more about Kenneth Samples.