Comparing Worldviews: Christian Theism vs. Metaphysical Naturalism

In his classic apologetic for the Christian faith, Orthodoxy, G. K. Chesterton tells of his conversion from the philosophy of the day as a matter of finding “a hole in the world” and discovering that Christian theology was “like a sort of hard spike” which “fitted exactly into the hole in the world” (71). Similarly, C. S. Lewis spoke for many when he confessed that “I believe in Christianity as I believe that the sun has risen: not only because I see it, but because by it I see everything else” (140). At the conclusion of his book The Reason For God, Timothy Keller writes: “I believe that Christianity makes the most sense out of our individual lives and out of what we see in the world’s history” (222). These men represent three different generations of the Christian faith, and all three came to believe in the truth of the Christian claim after carefully weighing the other alternatives. In particular, as distinguished Western academics, all three men weighed the Christian worldview against its most popular modern contender, metaphysical naturalism, and found the evidence in favor of Christianity.

Metaphysical naturalism is the view that there is “only a physical, natural world without gods or spirits” (Carrier 5). It is a predominately Western worldview which arose through the materialism of the Enlightenment, the empiricism of David Hume, and the evolutionary naturalism of the nineteenth century. As a worldview, it is “essentially an explanation of everything without recourse to anything supernatural”  (Carrier 4). In this sense, a naturalist is not simply someone who studies the natural world, but someone who denies the reality of anything beyond the natural world. It is thus an essentially atheistic view of the world. As Julian Baggini explains, “the arguments and ideas that sustain atheism tend naturally to rule out other beliefs in the supernatural or transcendental” (4). Metaphysical naturalism thus holds two basic beliefs: first, that “the scientific method is the only reliable path to knowledge,” and, second, that “matter (or matter and energy) is the fundamental reality in the universe” (Barbour 78). As Carl Sagan says it, “The Cosmos is all that is or ever was or ever will be” (4).

Metaphysical naturalism must not be confused with methodological naturalism. The later speaks simply of the scientific method of observation, while the former speaks of a particular worldview, a way of interpreting everything, and as such necessarily goes beyond the domain of scientific observation alone. In order to understand the mechanisms involved in the material world, the material world itself must be studied empirically, thus entailing methodological naturalism. But metaphysical naturalism entails the conclusion that only that which can be empirically verified exists.

In the twenty-first century West, Christian theism and metaphysical naturalism are probably the two ideologies that come into the most public conflict with one another. This conflict is often framed on a popular level as if it was a wholesale battle of faith vs. reason, or religion vs. science, yet such an analysis is far too simplistic, and fails to account for either the history of dialog between religion and science or the philosophical presuppositions which drive the conclusions of metaphysical naturalists. In order to give an accurate account, we must compare the two worldviews for what they are, which are competing answers to life’s most fundamental questions: Who are we? Where are we? What’s wrong? What’s the solution? These questions include but go far beyond the domain of science alone, for they deal ultimately with issues of purpose and meaning. But since the answers to these questions constitute a hypothesis that claims to account for our existence and experience of the world, in order to do justice to both accounts we must first consider the basic hypothesis which each offers.

Who are we? According to Christianity, we are made in the image of God, a special part of the creation that he made and called good (Plantinga 28-33; Wilkins 185-188). We are not animals. Our capacity to learn, love, create, and choose, and the wider impact that this unique dignity has on everything we touch, sets us markedly above the animal kingdom. Likewise we are not gods, but God himself has entrusted us with the task of wisely ruling over the rest of the created order. We are thus key actors in the cosmic drama of redemption (Gen. 1:26-31; Ps. 8:3-8). According to naturalism, however, we are merely complex machines, one species among many, more developed but no different in principle from any other advanced form of life. Our personalities are “an interrelation of chemical and physical properties we do not yet fully understand” (Sire 64). There is no divine goal or purpose to our existence; we happen to exist by a great cosmic coincidence, and eventually we will cease to exist altogether. Since there is no higher goal or purpose to our existence, the worth and quality of our brief lives are whatever we make of them.

Where are we? According to Christianity, we are living in the world created and sustained by the God we worship, standing in between the two climactic moments in his great plan of redemption (Plantinga 19-44; Wilkins 184-185). The whole world does not yet recognize him as the one true God. As a reflection of his love, God has given us the freedom to serve him or reject him, to believe him or ignore him, and many have thus chosen to turn their backs on the author of life, giving their allegiance instead to created things which are, at best, parodies of the truth, and at worst deeply dehumanizing distortions of it (Rom. 1:18-32). God’s kingdom and the kingdom of darkness thus exist for a time side by side, until the day when he will make all things new (Matt. 13:24-30). According to naturalism, by contrast, we are on a planet that at this time happens, by its own processes, to have the right ingredients for us to live and evolve into the thriving species we are today. Since there is no higher goal or purpose, however, there is no larger cosmic drama of which we play a part. The fact that we exist here and now is a remarkable (and, if our universe is alone, statistically improbable) fact, but it is nothing more than that. There is no greater meaning to history, just what we make of it (Sire 68-72; Palmer 160-61).

What’s wrong? According to Christianity, we have abused our calling as God’s image bearers. Instead of reflecting his wise and loving kingdom out into the world, we have turned in on ourselves. Aspiring to be gods, we have acted like animals, and all creation has suffered as a result of our rebellion (Plantinga 47-68; Wilkins 188-192). Death and decay, pain and violence—these are foreign invaders into God’s good creation, given free reign by the sin of men and women, spiraling through our history into deeply ingrained, systemic forces beyond our control (Genesis 3-11; Rom. 3:10-18). According to naturalism, however, nothing is ultimately wrong. Death and decay are not enemies; they are an intrinsic part of our world, and while pain and violence are perhaps regrettable from our vantage point, they are a necessary part of the evolutionary process. Since there is no God to whom we must all give an account, there is no such thing as sin. Morality is simply a social construct that enables us to get along together (Sire 72-76).

What’s the solution? According to Christianity, God himself has done what we could not. When we were all faithless, he was still faithful. Through becoming one of us, and sharing in our plight, he walked out the calling that we had all abandoned, demonstrating what it means to be truly human (Plantinga 69-100; Wilkins 192-200). By dying at the hands of sinful men, taking upon himself the judgment that we deserved but which he did not, he has exhausted the power of sin and death by rising from the dead, and he has thus opened wide the path to righteousness and life for all who come to him in faith and repentance. He will finish the good work that he started, making all things new at his appearing, and we anticipate that great act of restorative justice by living out the pattern laid out for us in his life, death and resurrection (Rom. 8; Eph. 1-2; Col. 1; 1 Cor. 15). According to naturalism, however, since there is no problem, there is no solution. We can work toward the further advancement and prosperity of our species, delaying our inevitable extinction, but this has no ultimate or lasting value. Many naturalists try to escape the nihilism of this conclusion, but all attempts to do so appear artificial and incoherent with the fundamental elements of the worldview itself.

Let’s consider briefly how these two contrasting hypotheses stand up to the data of human knowledge and experience. The naturalist account, we must admit, has the appeal of a relative simplicity which, by comparison, the Christian story lacks. Any explanation of reality that omits reference to the supernatural will inevitably be simpler than an explanation which includes such reference. But it seems that by omitting reference to anything outside of empirical verification, naturalism has gained simplicity at the great cost of excluding much of the data, since there is in fact a whole range of human experience, both in history and in the present, which does not submit itself to empirical verification. As Ian Barbour says it, “If science is the only acceptable form of understanding, explanation in terms of astronomical origins, evolutionary history, biochemical mechanisms, and other scientific theories will exclude all other forms of explanation. I would reply that science relies on impersonal concepts and leaves out of its inquiry the most distinctive features of personal life” (81). From the unrepeatable nature of history to our perception of beauty and moral obligation, the vast and multifaceted experience of human life simply cannot be reduced to the terms of scientific explanation alone. Thus the conclusion of John Polkinghorne: “From the practice of science to the acknowledgment of moral duty, on to ascetic delight and religious experience, we live in a world which is the carrier of value at all levels of our meeting with it. Only a metaphysical account which is prepared to acknowledge that this is so can be considered to be at all adequate” (19).

Of course, naturalists would contest whether such “data” really counts, which brings us to the underlying issue of epistemology. Historically speaking, Christian theism and metaphysical naturalism have held two contrasting accounts of how we perceive reality. These contrasting accounts lie at the heart of the debate between these two worldviews, since the decision we make about what counts as true knowledge decides to a large extent what kind of evidence we allow in court. These two accounts can be labeled logical positivism and critical realism, respectively.

Although its roots go back to the empiricism of David Hume, as a full-grown philosophy of knowledge logical positivism only came of age in the 1920s. And although it has now been “largely abandoned by philosophers, it has had a long run for its money in other spheres, not least those of the physical sciences” (Wright 33). The positivist position asserts that “scientific discourse provides the norm for all meaningful language,” and that the only things worthy of being called true are “empirical propositions verifiable by sense data” (Barbour 79). In other words, science alone is objective, while everything else is subjective. “[The norm] is presumed to be that human beings, with proper scientific controls available, have instant access to raw data about which they can simply make true propositions on the basis of sense-experience. Since it is obvious that not all human knowledge is of this type, the sorts of knowledge that break the mould are downgraded” (Wright 33). By this criterion, a whole range of human language and experience was thus “eliminated from serious discussion because they were not subject to the verification that science was said to provide” (Barbour 79).

This view of human knowledge has proven itself exceptionally frail, however. The blunt distinction which positivism makes between objective vs. subjective, and the stark either/or which results, is far too simplistic, revealing a naïve confidence in the presuppositions which accompany the observer's sense-experience, while at the same time holding a whole range of legitimate human knowledge to an impossible standard of scientific verification. N. T. Wright puts it well: “If knowing something is like looking through a telescope, a simplistic positivist might imagine that he is simply looking at the object, forgetting for the moment the fact that he is looking through lenses” (35). Granted that the subject matter of natural science allows it the luxury of testing theories against immediate results, not even science is an “objective” enterprise. As Barbour explains, “Sense data do not provide an indubitable starting point in science, for they are already conceptually organized and theory-laden. The interaction of observation and theory is more complex than the positivists had assumed. Moreover, the positivists had dismissed metaphysical questions but had often assumed a materialist metaphysics” (79). In doing this, positivist scientists “have failed to distinguish between scientific and philosophical questions. Scientists in their popular writings tend to invoke the authority of science for ideas that are not part of science itself” (81).

As Abraham Maslow said throughout his works, when all you own is a hammer, every problem starts looking like a nail. The trouble with metaphysical naturalism is that it makes science the hammer to which every question becomes a nail. “By definition, empirical science is characterized by methodological naturalism, but once it begins propounding metaphysical naturalism, it has overstepped its disciplinary boundaries” (Walton 155). In other words, as a methodology confined to the natural explanations of certain types of data, science is not ultimately equipped to answer the big questions of design and purpose. Metaphysical naturalism is therefore epistemologically reductionist.

In contrast with both positivism and relativism, the most distinctively Christian epistemology could be termed critical realism. As N. T. Wright explains it, critical realism “is a way of describing the process of ‘knowing’ that acknowledges the reality of the thing known, as something other than the knower (hence ‘realism’), while also fully acknowledging that the only access we have to this reality lies along the spiraling path of appropriate dialogue or conversation between the knower and the thing known (hence ‘critical’)” (35). To the critical realist, no human being has a God’s-eye view on reality. There is real truth to be had, and it really can be seen for what it is, but we all have particular perspectives, influenced by our own cultures, worldviews, brokenness, etc. This is unavoidable. Therefore we cannot accept an account in which we all assume proudly that we’re just seeing things exactly as they are, without coloring and (yes, at times) skewing them; and yet we do not use this as an excuse to slip lazily into a postmodern relativity where the truth ultimately can’t be seen through the haze and distortion of our own perspectives. The Apostle Paul expresses the balance of this view in the admonition, “Test all things; hold fast what is good” (1 Thess. 5:21).

A critical realist approach allows us to take a much fuller account of human knowledge than the blunt tools of logical positivism. And once we allow the wide range of data that positivism withholds from court, the case for Christian theism appears remarkably compelling. As Polkinghorne concludes, “Theism presents an adequately rich basis for understanding the world in that it readily accommodates the many-layered character of reality shot through with value. Scientific wonder at the rational order of the universe is indeed a partial reading of ‘the mind of God’… Yet there is much more to the mind of God than science will ever discover. Our moral intuitions are intimations of the perfect divine will, our aesthetic pleasures a sharing in the Creator’s joy, our religious intuitions whispers of God’s presence” (19).

Besides the satisfying account which it gives to the whole range of human experience, Christianity ultimately stands apart in its appeal to history, to the central claim that God became a man, died on a cross, and was resurrected from the dead three days later, being witnessed by hundreds before ascending into heaven. Of course, naturalists would object to this claim on the grounds of their own philosophical presuppositions. But the remarkable thing about Christianity is that it can actually substantiate its central claim with multiple, independent, coherent eyewitness testimonies. “If you don’t short-circuit the process with the philosophical bias against the possibility of miracle,” argues Keller, “the resurrection of Jesus has the most evidence for it” (219). Christianity thus presents a powerful challenge to the presuppositions of naturalism. It takes faith, just like everything else, but it is a reasonably motivated, defensible faith, not a blind faith.



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