The Classic Design Argument for God’s Existence

By Melissa Cain Travis

Is the design argument for the existence of God obsolete ? Many claim so, and the alleged demise is often traced back to the philosophy of David Hume, whose 1779  Dialogues Concerning  Natural  Religion excoriated  natural  theology. Agnostic philosopher of science Michael Ruse has remarked that when it comes to the classic design argument—the so-called “watchmaker thesis”—Hume’s critique knocked it down “like a house of cards.”1 Or so the story goes. What has gone under-appreciated, perhaps unnoticed, is the potent response that was offered by Hume’s contemporary, Thomas Reid. A fresh evaluation reveals that  the design argument for God’s existence remains a viable instrument in the apologist’s tool chest.

In his Natural History of Religion, Hume says that  “the whole frame of nature bespeaks an intelligent author;  and no rational enquirer can, after serious reflection, suspend his belief a moment” and “a purpose, an intention, a design, is evident in every thing.”2

Of course, Hume did not see this as any reason to think design perceptions reflected  the  truth  about the world—he  was  a thorough going skeptic. However, it is key to note that he viewed his critique as being independent of his skepticism.

The objections Hume presents in the Dialogues encompass both the  analogical and the inductive forms of the classical  design argument. Put simply, the analogical form points out features of some natural  phenomena that are similar to features of human artifacts and then concludes that since human artifacts are products of intelligent agency, the natural phenomena in question must also come from an intelligent agent. The inductive form bases the design conclusion up on all previous experience of human designers and their products . It claims that, be cause products with certain features are known, by uniform experience, to come from intelligent designers, it can be concluded that natural phenomena with artifact-like features also came from an intelligent designer. Hume’s critique of the former is that the analogy between human design products and natural phenomena (especially the universe itself ) is too weak , that the cases are not similar enough to justify concluding that  there is a mind behind the natural world , thus the argument for a designer based up on the features of the natural world is a very weak analogy. His contention against the inductive form of the argument is that we can only infer causes with which we have actual experience when attempting to explain known effects . Upon observation of complexity, harmony of parts, and adjustment of means to ends, we may postulate a designing agency, but only to the extent that  the object in question “has been experienced to proceed from that principle.”3  Past direct experience of the same species of cause is necessary if we are to infer that cause from any of its alleged effects .

It is not uncommon for to day’s opponents of design to employ the Hume an objections. Robert Pennock claims that as so on a s one attempts to move from a phenomenon in nature to an intelligent supernatural agent, the very concept of design “loses any connection to reality as we know it or can know it scientifically.”4  Pennock does not see how we could justify positing a cause of which we have no observational knowledge. Similarly, John Wilkins and Wesley Elsberry emphasize what they see as an “in-principle difference between rarefied and ordinary design inferences, based on the background knowledge available about ordinary, but not rarefied, design agencies.”5   In other words, without first-hand knowledge about a supernatural (“rarefied”) designing agent, we are unable to draw an analogy between that alleged cause and human designers, despite any similarities between human artifacts and qualities of nature. Iris Fry has also issued a Humean objection to design analogies, claiming that “if the intelligent agent is supernatural, it cannot be compared to humans.”6  Fry accuses design proponents of begging the question in favor of theism— assuming what they are attempting to prove by setting up an analogy between human intelligence and an alleged designer’s intelligence. 7

By way of response, advocates of the design  argument should consider the approach taken by Thomas Reid,  whose  lecture series on natural theology (1780)  includes rejoinders to Hume’s objections. Reid begins by giving a nicely detailed exploration of what he considers marks of designedness in the natural world . He describes man’s digestive and circulatory systems, each comprised of  specialized  parts that operate  harmoniously for a specific purpose, and the construction of the eye, “a small ball fixed in a socket [by which] we can perceive the fixed stars and the various objects around us by means of the refraction of the rays of light.”8

He  maintains that “it  would be impossible to enumerate every mark of wisdom” that can be observed in the animal kingdom.9

For Reid, “marks of wisdom” include both regularities in nature and the integration of necessary parts in living systems to achieve certain functional ends.

It may seem that Reid is simply defending the analogical design argument by describing and marveling over these “marks of wisdom” in nature ; but close examination of his language in the lectures and comparison with his terminology in An Inquiry into the  Human Mind on the Principles  of Common Sense demonstrate a decidedly two -pronged approach . According to Reid , belief in an intelligent artificer of the world is epistemically foundational, a belief  that is not reached by way of analogical or inductive reasoning ; it is what he famously refers to as a common sense belief. We trust such beliefs to contain accurate information about reality; even the skeptic who denies this must live as if it is so. The design conclusion is, according to Reid, one of these common sense beliefs, a conclusion we cannot avoid by virtue of how we are made. We simply see that there is this designedness in natural phenomena. In his Inquiry, he explains that no premises are involved ; the mind reacts to indicators in nature by forming an immediate belief. He holds that “the mind passes instantly to the thing s signified, without making the least reflection upon the sign, or even perceiving that there is any such thing.”10

Recall Hume’s similar recognition of man’s propensity to simply see design in nature ; the major point of divergence is that Reid believes these automatic  design  perceptions are  reliable  truth  indicators whereas Hume does not. Reid asserts that the existence of a designer necessarily follows from actual designedness, and therefore, belief in a designer is itself part of man’s first principle knowledge “learned neither by reasoning nor by experience.”11  Says Reid, “It is on this principle then, that my argument is grounded. There are clear marks of wisdom and design in the formation and government of the world, must the y not arise then from a designing cause?”12

Contrary to Hume’s skepticism, Reid’s common sense philosophy deems our faculties a reliable conduit of truth  about the external world; he points out a serious predicament that arises from Hume’s claim that these immediate perceptions are not reliable sources of truth and that reason alone should be trusted: “ Why, Sir, should I believe the faculty of reason more than that of perception; they came both out of the same shop, and were made by the same artist ; and if he puts one piece of false ware into my hands, what should hinder him from putting another?”13 Why think that human reason has access to truth any more so than human perception, since their ultimate origin is the same? Reid’s challenge holds whether the “shop” from which the human mind came is thought to be divine or natural. There seem to be only two options ; either trust both human faculties to a similar extent, or distrust them both entirely.

Contemporary skeptics of design may respond that the reason we cannot trust the design beliefs produced by perception is that we now have a defeater for agent-driven design: the full capability of unguided natural selection, acting upon random genetic mutations, to produce the appearance of design in living things. Hume made no such claim about the power of natural mechanisms ; in keeping with his skeptical epistemology, he expressed a staunch agnosticism based upon our finite knowledge of nature. Nevertheless, it is worth noting that Reid had a reply for the materialist allegation that natural processes are a sufficient explanation for the origin and features of natural phenomena, and it is a response that remains valid, despite any advances in evolutionary theory. Reid explains that a physical cause of a natural phenomenon in no way rules out a final cause— there being purpose and intention  behind the constitution of the phenomenon. He says, “The physical cause hunts out the laws of Nature from which the phenomena flow…but the final cause again hunts out the end which Nature had in view. Thus, the end of the eye is for seeing, the feet for walking, and so on.”14 Reid recognized the necessary link bet ween a phenomenon having a final cause and having an intelligent designer. Note that he is not using circular reasoning here ; rather, he is pointing out that the physical working s and/or origin of a phenomenon say nothing of its teleology, a point C.S. Lewis later made in Mere Christianity, when he said that “whether there is any thing behind the thing s science observes—something of a different kind—this is not a scientific question.”15

In addition to defending basic design beliefs and the analogical design argument, Reid directly challenges Hume’s objection to the inductive form of the argument. Hume contends that because we have no experience with a transcendent designer, we are not justified in inferring that species of cause from the observed phenomena of nature. In our uniform experience, argues Hume, there does seem to be a constant conjunction bet ween human designers and human artifacts, but that conjunction cannot be applied to nature’s origin. Reid heartily disagrees,arguing that inferring a designer from marks of design can quite  reasonably be  based upon  observed effects, and that these effects are sufficient g rounds for assigning certain attributes, such as wisdom and intelligence, to their cause. In fact, this is all we can do even in the case of human designers, because we do not actually have direct knowledge of human wisdom: “No man ever saw wisdom, and if he does not conclude from the marks of it, he can form no conclusions respecting any thing of his fellow creatures.”16  Thus, if one denies the validity of the design conclusion drawn inductively from marks of wisdom in nature, he must also deny the validity of the “other minds” conclusion drawn from the marks of wisdom in human products and behaviors.

For Reid, the designing intelligence responsible for the universe is God. Thus, his rejoinder runs head-on into another of Hume’s objections : that positing God as the mind behind the material world is unjustified anthropomorphism, and is degrading to the  Deity. Hume argues that imagining we can comprehend God, that we can have any understanding of his nature, is to bring him down to human level: “By representing the Deity as intelligible and comprehensible, and so similar to a human mind, we are guilty of the grossest and most narrow partiality, and make ourselves the model of the whole universe.”17 We cannot suppose that God’s rationality is any thing like ours, so we cannot presume that what our minds perceive as marks of design are any thing like the marks that would result from God’s mind. In his Natural History of Religion, Hume lamented this “universal tendency among mankind  to conceive all  being s like  themselves, and to transfer to every object, those qualities, with which the y are familiarly acquainted, and of which they are intimately conscious.”18

A successful design argument would, in Hume’s estimation, make God finite, since we are only justified in inferring , at most, the level of wisdom in a cause that we see in its effects.19 When we observe harmful or allegedly substandard natural phenomena, for instance, we must conclude that the designer of the world could not do better. But leaving aside the issue of natural evil, mankind cannot glean any knowledge of God from nature in the first place, as we are hopelessly limited by our imperfect human ideas and capacities.

Reid counters Hume’s contention with two analogies. First, suppose you went on a journey, and along the way stopped to ask a man for directions to a certain town. The man responds succinctly and correctly. However, this would not allow you to conclude that the man did not know any thing about the local geography beyond what he verbally indicated. Reid asks, “Am I therefore to conclude that his understanding just enable him to answer my question and neither more nor less? Surely this would be absurd—the natural conclusion is, that he has such a degree, how much more I do not know.”20 Similarly, suppose you were to converse with a man for only half an hour upon a scholarly subject, and discover that he is quite knowledgeable on the topic. You would not be justified in concluding that what he said over the course of that half hour exhausted his knowledge on the topic.21 This being the case, one cannot observe the universe and its limitations or so -called imperfections and conclude a designer of finite wisdom and power.

But what of the first part of Hume’s objection—that anthropomorphizing God, making him in any respect comprehensible, is unjustifiable? Reid openly acknowledges our human constraints:

The best notions of the divine Maker which we can form are imperfect and inadequate and are all drawn from what we know of our own Mind. We cannot form an idea of any attribute intellectual or moral as belonging to the deity, of which there is not some faint resemblance or image in ourselves.22

Yes, our conceptions are “imperfect and inadequate,” but Reid contends that there is a key correspondence between the mind of man and the mind of man’s maker, a “resemblance or image” that we bear. First of all, God’s attribute of omniscience can be concluded by reason, as it is a perfection and God is defined as the most perfect being.23  It follows from this that God has perfect knowledge of mankind: “ The Supreme Being knows all his creatures and all their qualities…the artificer knows his own workmanship.”24 If this is so, then God knows all that man knows and he knows the manner in which man knows it. God and man share the property of being rational knowers.25  There is overlap in their knowledge and the nature of that knowledge, such that man has access to some of the content of God’s knowledge. In the middle of his discussion of the marks of wisdom in nature, Reid touches on this idea . He pauses to ask, “He that made the eye, shall he not see ? He that made the ear shall he not hear ? He that gave a man understanding shall he not understand?”26

In order to deflect the  anthropomorphism critique,  the  design proponent only needs to  establish that the designer ’s rationality has some shared property and content with man’s and that this rationality is somehow exhibited in the created order. One of Reid’s characterizations of “marks of design” in nature is directly relevant here. In his discussion of astronomy, he highlights Newton’s theory of planetary motion as an example of rational precision in nature :

For Newton  has demonstrated that  supposing this  power [gravity] to take place, then the consequences would be, that this tog ether with a projectile force will make them describe elliptical  curves, and that  by this law the y would describe equal areas in equal times and that the square of the periodic times would be in proportion to the cubes of the distances. Thus we see the whole system regulated by exact mathematical rules. We see those producing the most accurate and constant operations. Now can we seek strong er marks of wisdom and design than this?27

He goes on to compare the gravity-driven, clockwork solar system to  the  multi-part,  finely-tuned  mechanism of a watch,  which  is governed by one great spring and, incidentally, produced by a skillful agent.28  What is significant here is that Reid emphasizes the mathematical nature of the laws governing planetary motion, as this is not something that we simply perceive with our sensory faculties; rather, it  is a quality we discover through rational investigation. This shows that he was not dismissive of efforts to reason to design from certain evidences. Perhaps a viable response to the Humean anthropomorphism objection is that, rather than assigning human qualities to the Creator, the design proponent is discovering reflections of the Creator’s qualities in man and the physical world.

As Planting a puts it, “God created both us and our world in such a way that there is a certain fit or match bet ween the world and our cognitive  faculties…a  match that  enables us to  know something , indeed a great deal, about the world–and also about ourselves and God himself.”29

Why   should  there  be  this  strange  resonance  bet ween  man’s rationality and the deep structure of the natural world if there is no real design behind things? Naturalistic evolutionary explanations are woefully inadequate ; the aptitude for higher abstract mathematics, for example, has no discernable survival value, and, as Planting a has humorously noted, no apparent sexual selective advantage, either : “ What prehistoric female would be interested in a male who wanted to think about whether a set could be equal in cardinality to its power set, instead of where to look for game ?”30 The alternative naturalistic thesis, that  this higher aptitude  is a spin-off of the evolutionary process, “sounds pretty flimsy, and the easy and universal availability of such explanations makes them wholly implausible” says Plantinga .31

However, positing an intelligent designer of both man and the rest of the  world has great explanatory power ;  it  bring s a coherence to  the  entire  picture.  The  harmony  bet ween man’s aptitude  for mathematics-driven scientific  discover y  and  the  applicability  of mathematics to the cosmos loses none of its grandeur, but much of its mystery in light of a three-way resonance bet ween God’s mind, the mind of man, and the created order.

Today ’s defendants of the design argument would greatly benefit from an awareness of Reid’s approach. The inclusion and development of Reidian ideas in the works of eminent philosophers, such as Alvin Planting a , attest to Reid’s enduring value for the project of natural theology. Humean objections turn  out to lack much of the force that has been attributed to them and contemporary accusations of question-begging  are  effectively dissolved. Reid’s  common sense epistemology, his arguments for the reliability of human cognition, the nature of the material world (the living and nonliving parts), and what we can know about the nature of the Creator based upon the created order bring a remarkable coherence to the design paradigm.

1 Michael Ruse, Darwin and Design (President and Fellows of Harvard college, 2003), 27.

2 David Hume, The Natural History of Religion, 1. Accessed July 14, 2015 at

3 David Hume, Dialogues Concerning Natural Religion, in Classics of Western Philosophy

7th edition, ed. Steven Cahn (Indianapolis : Hackett, Inc.: 2006), 863.

4 Robert Pennock, Intelligent Design Creationism and Its Critics (MIT: 2001), 654.

5 John Wilkins and Wesley Elsberry, “ The Advantages of Theft over Toil : The Design

Inference and Arguing from Ignorance,” Biology and Philosophy 16 (November 2001),


6 Iris Fry, The Emergence of Life on Earth (New Brunswick, NJ: Rutgers University Press :

2000), 206.

7 Ibid., 205.

8 Thomas Reid, Thomas Reid’s Lectures on Natural Theology ed. Elmer Duncan

(Washing ton, D.C.: University Press of America , 1981), 35-37, 40.

9 Ibid., 35.

10 Thomas Reid, An Inquiry into the Human Mind on the Principles of Common  Sense ed. Derek Brookes (University Park, PA: Pennsylvania State University Press, 1997), 81.

11 Reid, Lectures, 54.

12 Ibid.

13 Reid, Lectures, 169.

14 Reid, Lectures, 55.

15 C.S. Lewis, Mere Christianity (New York : Harper One, 2001), 23.

16 Reid, Lectures, 56.

17 Hume, Dialogues, 869.

18 Hume, History of Natural Religion, 7.

19 Hume, Dialogues, 890.

20 Reid, Lectures, 92.

21 Ibid.

22 Ibid., 2.

23 Ibid., 75.

24 Ibid.

25 Alvin Plantinga, Warranted Christian Belief, 24 and 65. Accessed July 14, 2015 at

26 Reid, Lectures, 41. Allusion to Psalm 94:9.

27 Ibid., 21.

28 Ibid.

29 Alvin Planting a , Where the Conflict Really Lies (New York : Oxford University Press,

2011), 269.

30 Ibid., 287.

31 Ibid.

[Editor’s Note: Atheism image from Jan Matejko’s Stańczyk, 1862, found at  Wikipedia Commons.]