The analogical design argument
We begin our study of natural theology with design arguments, not because they are logically prior to the other arguments for Godâs existence, but because they are grounded in so common and widespread an experience â that of beholding the complexity, grandeur and apparent design of the world around us. How many of us have cast a heavenward glance at the star-studded sky on a spectacularly clear night and been moved to the thought âsurely this could not have come about by sheer accident, but must be the work of some supernatural beingâ? Or, for those whose wonder is moved by the microcosmic, how many of us lazily stretched out on a lawn have fixed upon a single blade of grass, contemplated the cellular machinery necessary to produce chlorophyll, and been moved to the same thought? Surely, our initial sentiments suggest that the world and all it contains could not have arisen by accident, that it must be the work of an intelligent agent; and who better than God to produce a world of such scale and intricacy?
Whittaker Chambers, who gave important evidence against convicted Communist spy Alger Hiss during the Cold War, wrote in his book Witness:
But I date my break [with the Communist Party] from a very casual happening. I was sitting in our apartment in St. Paul Street in Baltimore. It was shortly before we moved to Alger Hissâs apartment in Washington. My daughter was in her high-chair. I was watching her eat. She was the most miraculous thing that had ever happened in my life. I liked to watch her even when she smeared porridge in her face or dropped it meditatively on the floor. My eye came to rest on the delicate convolutions of her ears â those intricate, perfect ears. The thought crossed my mind: âNo, those ears were not created by any chance coming together of atoms in nature (the Communist view). They could have been created only by immense designâ. The thought was involuntary and unwanted. I crowded it out of my mind, but I never wholly forgot it or the occasion. I had to crowd it out my mind. If I completed it, I should have had to say: Design presupposes God. I did not know then, but at that moment, the finger of God was first laid upon my forehead.
(Quoted in Gardner 1983: 196â7)
Even Immanuel Kant, thought by many to be one of natural theologyâs most forceful critics, nevertheless says of the argument:
This knowledge [of nature] again reacts on its cause, namely, upon the idea which has led to it, and so strengthens the belief in a supreme Author [of nature] that the belief acquires the force of an irresistible conviction. It would therefore be not only uncomforting but utterly vain to attempt to diminish in any way the authority of this argument. Reason, constantly upheld by this ever-increasing evidence, which, though empirical, is yet so powerful, cannot be so depressed through doubts suggested by subtle and abstruse speculations, that it is not at once aroused from the indecision of all melancholy reflection, as from a dream, by one glance at the wonder of nature and the majesty of the universe â ascending from height to height up to the all-highest, from the conditioned to its conditions, up to the supreme and unconditioned Author [of all conditioned beings].
(Critique of Pure Reason A624/B652; 1961: 520, emphasis added)
Kant is careful to distinguish between the purely intellectual and the psychological force of the natureâs apparent design. While he thought the âsubtle and abstruseâ speculations of philosophy could not fashion a logically irrefutable proof for Godâs existence, he nevertheless thought that the evidence of design moved the mind to âirresistible convictionâ psychologically, or through what was called by Thomas Reid, ânatural signsâ.1
The experience of apparent design, from the microcosmic to the macrocosmic, from the structure of single cells to the swirling stars of the Milky Way, prompts us to wonder whether the cosmos is the work of God. And, as wonder at the worldâs order gives rise to philosophical thought, it has fostered a family of arguments known as âteleologicalâ or âdesignâ arguments. William Paley, an eighteenth-century English philosopher and theologian, thought the evidence of design could be marshalled into a decisive argument for Godâs existence. Likening the world to a watch, Paleyâs version of the argument from design trades on an analogy between machines and the universe. Suppose one were to stroll along the shore and there find a beautiful gold watch keeping perfect time. Even if one lacked prior acquaintance with watches, one would not for an instant suppose that the watch had been accidentally assembled by the waves and tossed up onto the beach. We obviously think that objects of such complexity and apparent purpose â call them teleological mechanisms â cannot have come about accidentally, but only through the handiwork of some intelligent agent. Does not experience teach us uniformly that when we find teleological mechanisms whose parts appear framed and put together for a purpose â cameras, computers and cars being good examples â they are the work of intelligent agents and not the products of random or accidental forces? How much more, then, should this sentiment be strengthened as we consider that the worldâs subtlety, complexity and size far surpasses that of a watch.
Paleyâs reasoning employs a very common principle: where we see like effects, we reasonably infer like causes. This principle lies at the heart of all inductive reasoning and underlies much scientific research. A doctor, let us suppose, examines a patient and detects symptoms A, B and C, and blood tests and other diagnostic measures indicate disease D. Later in the day, the same doctor encounters additional patients with the same symptoms, and again tests point to disease D. When the sixth patient walks into her office displaying the very same symptoms, she reasonably infers disease D even in advance of results from diagnostic tests. Teleological mechanisms such as cars, cameras and computers all exhibit the harmonious interplay of parts, the means-to-end adaptation that bespeaks the work of intelligent agents. The universe, says Paley, displays these very same features or complexity and organization to a magnificent degree. In keeping with the principle that like effects presuppose like causes, is it not reasonable to suppose that the universe is the work of an intelligent agent?
David Hume, the famous eighteenth-century philosopher and religious sceptic, with his characteristic sparkling prose and evident wit, criticized arguments such as Paleyâs to devastating effect in his Dialogues Concerning Natural Religion. Hume (or Philo, thought by many to speak for Hume) objects to this analogical form of design argument on three main grounds. First, he thinks the analogy drawn between a watch and the world is weak. In order to say that with any confidence that the world resembles the watch, that teleology pervades the universe, we would need much more extensive knowledge of the vast reaches of the universe than we have. But we lack exhaustive knowledge of what is transpiring throughout the entire cosmos throughout all time. Perhaps chaos reigns in parts of the universe with which we are not yet acquainted. Perhaps the law-like regularities we presently observe are an aberration of the last couple of million years, and at other times past or yet to come, disorder will prevail.
Imagine going into an immense warehouse filled with thousands of shelves of books stretching from floor to ceiling and, upon inspecting one shelf, you observe that its books are alphabetically arranged. You could not, with intellectual propriety, conclude on the basis of that scant survey, that the rest of the books were also alphabetically arranged. (Contemporary science, however, gives us reasons Hume lacked to think that the laws of the universe are uniform throughout.) Moreover, the similarities between the world and the watch are too few. While each has multiple parts that move together in a coordinated way, we cannot easily assign a function to the universe. Washers wash, dryers dry, toasters toast; what does the universe do? Produce and sustain life? If physicists are correct to think that our sun, along with all the other stars, will be depleted of its life-giving energy and that life as we know it will one day be unsustainable, then the universe would appear to be, as much as anything else, a colossal engine of death!
Even if we grant that the universe resembles a watch by being ordered throughout, the argument still fails to establish the existence of the omniscient, omnipotent, omnibenevolent God of theism. If we suppose, as Paley does, that where we find similar effects we should postulate similar causes, then we cannot conclude that the designer of the universe is one, still exists, is infinite or, more disturbingly, is morally perfect.
To appreciate Humeâs point, consider the pyramids of Egypt â immense and impressive architectural achievements. As such, they had multiple designers, all of whom are dead, none of whom were infinite in power and, given the wages and benefits given to their labour force, they fell far shy of perfect goodness. Now by strict parity of reason, something the size and age of the universe should incline us still more to doubt the current existence of a single being who created it. More disturbingly, says Hume, human wickedness and the diseases, plagues and pestilence that beset human existence, hardly betoken the efforts of a supremely good creator. Our universe, if designed, is something of a jalopy, lurching down the road in fits and starts, and far from the sleek, stylish, smooth-running Rolls Royce of a universe we would expect from an infinite being.
Finally, Hume further impugns Paleyâs comparison of the world to a watch or knitting loom by suggesting it might just as readily be compared to vegetative life, which appears to have the ingredients of its organization and development within itself. In thinking that foreshadows Charles Darwin, Hume repeatedly suggests in the Dialogues that the organization and development of the universe is due to what he calls âhidden springs and principlesâ.
Thought, design, intelligence, such as we discover in men and other animals, is no more than one of the springs and principles of the universe, as well as heat or cold, attraction or repulsion, and a hundred others, which fall under daily observation. It is an active cause, by which some particular parts of nature, we find, produce alterations on other parts.
(Hume 1993: 49)
Hume is here gesturing in the direction of a natural rather than a supernatural explanation for the worldâs displaying the order and organization that is does. Hume could not, however, provide a satisfactory explanation for how natural forces such as gravity, heat, and magnetism could give rise to such complex creatures as human beings.
What Hume could only hint at, Darwin named and described in his famous 1859 work, On the Origin of Species. The structure, organization and development of all living things is due to replicating cells, random genetic mutation and natural selection, the essential elements of evolutionary explanations. Very roughly, the theory claims that natural organisms occasionally undergo random genetic mutation, resulting in some feature that other members of its kind lack: additional receptor sites on a cell wall, a longer neck or colour vision. Sometimes these adaptations prove favourable for survival in the particular environment in which the organism finds itself. The creature serendipitously finds itself in an environment where its mutation gives it greater access to food or makes it better able to elude predators. More often than not, however, these mutations are not adaptive. As Stephen Jay Gould points out, the Burgess Shale by itself contains the remains of more creatures long extinct than presently dot the face of the Earth (Gould 1989). But when random changes and environment cooperate to allow the creature to elude predators and compete for scarce resources more successfully than other members of its kind, its genetic material is more likely to be passed on to future generations.
Critics of the teleological argument deny that natureâs work resembles that of a watchmaker, and think instead that appeals to intellectual agency should give way to blind chance. Richard Dawkins happily accedes to this conclusion and describes natureâs processes thus: âIt has no mind and no mindâs eye. It does not plan for the future. It has no vision, no foresight, no sight at all. If it can be said to play the role of watchmaker in nature, it is the blind watchmakerâ (Dawkins 1986: 5). Elsewhere, Dawkins tells us: âThe universe has precisely the properties we should expect if there is, at bottom, no design, no purpose, no evil and no good, nothing but blind pitiless indifference ⌠DNA neither knows or cares. DNA just is. And we dance to its musicâ (Dawkins 1995: 133).
Logically, we are not stuck with just the two alternatives thus far surveyed, Paleyâs robust theism or the bleak naturalism of Dawkins. It is strictly logically possible, for instance, that pantheism is true, that the universe in its totality is itself divine, and somehow contains the principles of its organization and development within it, as Hume hints. Perhaps some finite creative force such as Platoâs demiurge created the universe. While any number of explanations are logically possible, we will continue as though the two leading explanations for the order and organization of the universe are God or blind chance.
The argument from irreducible complexity
Versions of the teleological argument based on an analogy between the world and machines faced formidable objections from Hume, but other versions of the design argument have been formulated that claim to escape these problems. We shall look briefly at three efforts to update the general thrust of the design argument. The first is âthe argument from irreducible complexityâ, powerfully forwarded by biochemist Michael Behe in his book Darwinâs Black Box (1996).2 In a nutshell, Behe claims that a tiny âmolecular machineâ such as the flagellum (tail) of the sperm cell and bacteria, is so elaborate, and the relationship of its parts to each other and to the cell that it propels so interdependent, that they could not have arisen in the way current evolutionary theory suggests. Darwin himself recognized the problem posed for his theory by irreducibly complex mechanisms. He writes: âIf it could be demonstrated that any complex organ existed which could not possibly have been formed by numerous, successive, slight modifications, my theory would absolutely break downâ (quoted in Behe 1996: 39). Behe claims to have identified precisely the sort of complex biological organisms and processes Darwin feared.
To understand the concept of an irreducibly complex machine, Behe bids us consider the humble mousetrap. It is a very simple mechanism, consisting of a spring, a hammer, a triggering device and a platform to hold the parts in place. The important point is that if you take away any one of the parts, the mousetrap will not function; it works either with every part present, or it does not work at all. Moreover, the individual parts have the function they do only when properly configured with the other parts of the trap; the bare hammer or triggering mechanism, lying off by themselves, have no function whatsoever. The irreducible complexity of the bacterium flagellum, the whip-like tail that propels the cell is even more dramatic, says Behe. This remarkable corkscrew-hair-like appendage acts like a propeller on an outboard motor, is fuelled by a delicate mixture of some thirty or so proteins, and includes a drive shaft, universal joint, bushings and bearings, rotor and a stator. According to Behe, these parts could not have developed their various functions while disconnected from one another, and then somehow have been cobbled together in the random and incremental way proposed by evolutionary theory. The better explanation, says Behe, is that these cellular structures arose as they did by benefitting from the guidance of intelligent agency.
Needless to say, since the publication of Beheâs book, microbiologists have risen to the challenge, offering explanations of how the flagellum might have arisen along standard evolutionary lines. Kenneth Miller, professor of cell biology at Brown University, disputes the claim that the flagellum is irreducibly complex, noting the resemblance between the flagellum and a needle-like appendage that salmonella bacteria possess to inject toxins into host cells (see Miller 2000).3 These needle-like structures share many elements in common with the flagellum, although they lack the proteins that propel the flagellum. The important point to grasp is that, if Miller is correct, the flagellumâs parts would not be useless were they disconnected and thus could later be recruited for a new use. While Miller admits that this is not a complete explanation, still less does it explain how these individual parts came to be, it nevertheless suggests that nature is more resourceful at combining existing biological parts for new purposes than Behe believes.
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