Contemporary Thomists such as Francis Beckwith,Footnote 1 William Carroll,Footnote 2 Edward Feser,Footnote 3 Marie George,Footnote 4 Ernan McMullin,Footnote 5and Michael Tkacz,Footnote 6 to name only a few, have been very dismissive of what has come to be known as ‘intelligent design.’Footnote 7 In their view, those attracted to the intelligent design movement display an inadequate understanding of the doctrine of creation and, as a result, fall victim to a ‘pathetic “God of the gaps” strategy.’Footnote 8 What is needed, they argue, is a proper understanding of God’s relation to creation as articulated by St. Thomas.

These writers point out that, in Thomas’s view, creation is to be understood as the complete dependence of all contingent being upon God. Created beings could not exist if God did not cause them to be.Footnote 9 Such beings possess real causal powers inherent in their created natures, but are totally dependent upon God for their existence.Footnote 10 Once this is realized, it can be clearly understood that ‘no explanation of evolutionary change, no matter how radically random or contingent it claims to be, challenges the metaphysical account of creation, that is, of the dependence of the existence of all things upon God as cause.’Footnote 11

It is on the basis of this distinction between God’s primary causality and the secondary causality of created beings that these Thomists are typically dismissive of intelligent design theorists. William Carroll, for example, asserts that defenders of ‘irreducible complexities’ think that divine agency must manifest itself in gaps of nature, writing that, ‘to insist that creation must mean that God has periodically produced new and distinct forms of life is to confuse the fact of creation with what Aquinas would call the manner or mode of formation of beings in the world.’Footnote 12 Similarly, Michael Tkacz takes intelligent design proponents to task for presumably thinking that creation requires that God by direct divine action has periodically produced new and distinct forms of life.Footnote 13 He goes on to assert that.

God does not intervene into nature … Our current science may or may not be able to explain any given feature of living organisms, yet there must exist some explanatory cause in nature. The most complex of organisms have a natural explanation, even if it is one that we do not now, or perhaps never will, know (emphasis added).Footnote 14

To think that God acts directly in nature is to commit the ‘Cosmogonical Fallacy’Footnote 15 of confusing primary and secondary causation, thus reducing God to just another agent within the world, rather than the Creator to which the world owes its existence. Consequently, any gaps in explanations of living things in terms of natural causes must be regarded simply as epistemological difficulties to be overcome, not as evidence of divine intervention into nature.Footnote 16 That God would create living beings indirectly through secondary natural causes is a sign of God’s greatness, since ‘getting non-intelligent beings to participate in the production of the world is more difficult than doing everything oneself.’Footnote 17

In assessing this apparently damning indictment of the intelligent design movement, a number of points need to be made. First, it bears emphasis that the focus of intelligent design theory is much narrower than commonly portrayed by these critics. Its goal is to evaluate scientific evidence as regards the role of intelligent agency in the origin and development of life. As such, it ‘holds the conviction of design much more strongly than a conviction about the identity of the designer.’Footnote 18 Intelligent design theorists are careful to distinguish the question of whether something is designed from the question of the identity of the designer. Thus William Dembski notes that ‘intelligent design is modest in what it attributes to the designing intelligence…design theorists recognize that the nature, moral character and purposes of this intelligence lie beyond the competence of science and must be left to religion and philosophy.’Footnote 19 It is certainly true that recognizing design in nature leads very quickly to the question of who is responsible for such design and that belief in God is hard to avoid if one takes seriously the latter question. Equally, if one believes its God, it is unsurprising that one is open to detecting design in nature. It is thus hardly surprising that most, though not all, intelligent design proponents are theists. They insist, however, that the question of whether design is evident in living things is logically distinct from the question of the identity of the designer(s).Footnote 20

Second, the assumption that proponents of intelligent design are either unaware, or take no notice, of the distinction between God’s primary causation of all contingent being and the operation of secondary created causes is unjustified. I am acquainted with a number of the leading theorists of the movement and have heard others speak. In my experience, they are quite aware of the distinction and willing to grant that God can and does work through the instrumentality of secondary causes. For writers such as Carroll to portray intelligent design advocates as holding the simplistic view that divine agency must manifest itself through gaps in nature amounts to a misrepresentation and caricature of their position.

Third, that God works entirely through the instrumentality of secondary causes in bringing about the origin and development of living beings cannot be simply assumed. Given the actual nature of the created physical universe, this might prove to be logically impossible;Footnote 21 but leaving aside this caveat, to assert that God could create living things indirectly through secondary causes scarcely implies that He did in fact do so. It is one thing to claim that God could choose to create in a certain way, quite another to insist God had, or definitely did choose, to create in that way. To insist, as do Carroll and Tkacz, that the God who creates and sustains the natural order cannot be thought ever to intervene in that order, seems strange. It is fair to suggest that they owe some explanation of why the doctrine of creation ex nihilo, that is to say the doctrine of the universe’s absolute dependence upon God, justifies such a claim.Footnote 22

Ironically, the pronouncements of contemporary Thomists frequently resemble more the claims of deists than they do the claims of Thomas, their professed inspiration. It is not difficult to find parallels in the writings of eighteenth-century deists to Tkacz’s assertion that God does not intervene in nature, Carroll’s insistence that any gaps in explanations of living things in terms of natural causes must be regarded simply as epistemological difficulties to be surmounted, and George’s claim that the greatness of God suggests that He would choose to create living beings entirely through the instrumentality of secondary causes. Thomas Chubb, for example, remarks ‘that God, at the creation, put the natural world under the direction of certain laws;…the divine energy, or those immediate acts of God’s power, by which the system of nature is kept together, and continually upheld and preserved…[is] a part of God’s general providence.’(emphasis in the original)Footnote 23 Similarly, we find Thomas Morgan praising God’s ‘Government and Direction of Nature, by general Laws, [that]…obtain and secure the best Order and Constitution of Things upon the Whole, without obliging the Deity, or Author of Nature, to suspend his Laws, or alter his prescribed Rules and Measure of Action, by frequently interposing on particular incidents and emergencies,’Footnote 24 and going on to assert that

we do not find, that the Deity, or universal Cause and Agent, ever suspends or alters the mechanical Properties of Matter, the Laws of communicating Motion, the Forces and Directions of the heavenly Bodies…or, in a Word, any of the general Laws of Nature … Such a Supposition would be unworthy of God, as the Creator and Governor of the World, and the universal Cause, Preserver, and Director of Nature.Footnote 25

By contrast, Thomas is very willing to talk of God directly intervening in the course of nature. Thus, we find him asserting that ‘God, at the first establishment of things, brought all things immediately into being by creation…He is able immediately to move anything to any effect without intermediate causes’Footnote 26 and that ‘although the order implanted in things by divine providence represents in its own way divine goodness,…the divine will is not limited to this particular order of causes and effects in such a manner that it is unable to will to produce immediately an effect in things here below without using any other causes.’Footnote 27 In point of fact, far from being embarrassed by admitting divine intervention in the natural order, Thomas gives it special status, observing that

the order of providence does not fail, or suffer change, because of such an event…divine power can sometimes produce an effect, without prejudice to its providence, apart from the order implanted in natural things by God. In fact, He does this at times to manifest His power. For it can be manifested in no better way, that the whole of nature is subject to the divine will, than by the fact that sometimes He does something outside the order of nature. Indeed, this makes it evident that the order of things has proceeded from Him, not by natural necessity, but by free will.Footnote 28

The late Ernan McMullin allowed for the possibility of divine intervention but argued that such intervention is best understood as occurring only in salvation history and that any intervention in cosmic history is antecedently improbable on theological and philosophical grounds.Footnote 29 Once again, it bears emphasis that such a view is far removed from what Thomas thought. We find that, influenced by Aristotle,Footnote 30 Thomas drew a distinction between plants and animals that reproduce themselves, and those that he thought were spontaneously generated from dead or decaying matter by the power of the heavenly bodies. He referred to animals that reproduce themselves as animals generated from seed. As regards such animals, he writes,

there are, however, many sensible forms which cannot be produced by the motion of the heaven except through the intermediate agency of certain determinate principles pre-supposed to their production; certain animals, for example, are generated only from seed. Therefore, the primary establishment of these forms, for producing which the motion of the heaven does not suffice without their pre-existence in the species, must of necessity proceed from the Creator alone.Footnote 31

Further, in contrast to George’s observation that design and chance are not exclusive of one another and therefore that chance can play a role in originating complex life,Footnote 32 we find Thomas arguing that,

those things whose distinction from one another is derived from their forms are not distinct by chance, although this is perhaps the case with things whose distinction stems from matter. Now, the distinction of species is derived from the form, and the distinction of singulars of the same species is from matter. Therefore, the distinction of things in terms of species cannot be the result of chance; but perhaps the distinction of certain individuals can be the result of chance.Footnote 33

One finds in contemporary Thomists’ quick dismissals of the intelligent design movement frequent reference to the presumed fallacy of intelligent design theorists positing a ‘God of the gaps.’ At one level, it is sufficient to point out that intelligent design theorists are careful, as has already been noted, to distinguish the question of whether something is designed from the question of the identity of the designer(s) and insist that their goal, qua intelligent design theory is to identify instances of design, not settle the question of the designer(s) identity or attributes.

At another level, however, it is clear that many, though certainly not all, proponents of intelligent design, are further prepared to argue that the design they detect in living things is best explained on the basis of direct intervention of God at various points in life’s history. If such interventions have in fact taken place, then it is to be expected that there will be gaps in explanations in terms of natural, that is to say, secondary, causes. They argue that the fact that such gaps are abundantly evident is reason to take seriously that such interventions have occurred.

This, however, it is charged, is to commit the ‘God of the gaps’ fallacy. That it has not been shown that an explanation in terms of natural causes can be invariably provided is not in itself a positive argument for supernatural intervention. Proponents of intelligent design are, therefore, guilty of a form of argumentum ad ignorantium, which is to say, they are guilty of arguing that because it has not been proven that complete natural explanations of the origin and development of living beings are possible they are, therefore, entitled to conclude that supernatural intervention has taken place, without ever providing positive evidence for such intervention.

There are at least two reasons to question whether this charge of fallacious reasoning on the part of intelligent design theorists is justified. First, ex silentio arguments are frequently used in historical research, psychology recognizes the reasonableness of ‘lack-of-knowledge’ inferences made by experimental subjects, the natural sciences employ the concept of ‘negative evidence’ and philosophers of science recognize the validity of certain types of ‘no-see-um’ inferences. It will not do to label any appeal to negative evidence in the form of the inability of natural explanations to account for living beings as automatically committing the fallacy of argumentum ad ignorantium.Footnote 34 Given a thorough enough search, the absence of evidence can justifiably be taken as evidence of absence.Footnote 35

Second, and more fundamentally, it is not the case that intelligent design advocates provide no positive evidence in support of their position. Living beings contain vast amounts of specified information in their structures. Structures that manifest redundant order, for example, crystals, or simply complexity, for example, mixtures of random polymers, are easily found in nature, but none of them exhibit the specified complexity that exists in DNA, RNA, and proteins.Footnote 36 It is not simply that such specified complexity recalcitrantly resists explanations in terms of any known natural causes, but rather that our experience is that intelligent agency unfailingly plays a causal role in the production of structures that exhibit specified complexity. Thus Stephen Meyer notes that,

the inadequacy of proposed materialistic causes forms only part of the basis of the argument for intelligent design. We also know from broad and repeated experience that intelligent agents…produce information-rich systems…Experience teaches that whenever large amounts of specified complexity or information are present in an artifact or entity whose causal story is known, invariably creative intelligence – intelligent design – played a role in the origin of that entity. Thus, when we encounter such information in the large biological molecules needed for life, we may infer – based on our knowledge of established cause-and-effect relationships – that an intelligent cause operated.Footnote 37

It might in fact be argued that Thomists such as Carroll and Tkacz are guilty of fallacious reasoning in the form of begging the question. To assert that gaps in purely natural explanations of living beings ‘can only be epistemological difficulties to be overcome’Footnote 38 and that even the most complex of organisms must have a natural explanationFootnote 39 is to take for granted a claim that needs to be defended, not simply assumed. It is one thing to argue that all contingent being relies upon God for existence, quite another to argue that God never directly intervenes in the natural order He upholds. The assumption on the part of many Thomists that arguing for the first of these propositions justifies affirming the second is a non sequitur. Certainly, as has already been noted, it is at odds with Thomas’s own position.

Feser, like Carroll and Tkacz, takes those attracted to intelligent design to task as committed to what he terms a ‘pathetic “God of the gaps” strategy.’Footnote 40 Such strong language is strange, given that he is prepared to admit that for some biological structures it may be the case they are ‘overwhelmingly unlikely to have arisen through impersonal processes.’ Puzzlingly, he immediately qualifies this admission, asserting ‘that this is ‘God of the gaps’ reasoning that is constantly vulnerable to be overthrown by further scientific research, which may well reveal (as it has done in the past) mechanisms by means of which what seems irreducibly complex can be accounted for in terms of more simple, impersonal unthinking forces of nature.’Footnote 41 He goes on to assert, however, that no follower of Aquinas ‘could or should accept so-called ‘theistic evolutionism,’ if that is understood as entailing that every aspect of the biological realm, including every aspect of human nature, can be explained in terms of purely physical processes like natural selection.’Footnote 42 He appears, therefore, committed to the view that attempted explanations of living beings in terms of unconscious and unintelligent material causes will invariably contain gaps that are not simply the result of our ignorance of how such causes operate.

Despite his rhetorical use of the ‘God of the gaps’ objection, Feser’s real quarrel with intelligent design proponents is not primarily over whether, due to the exercise of directive intelligent agency, there exist genuine gaps in purely material explanations of living things. Rather, it has a deeper root. Feser is convinced that those in the intelligent design movement ‘have sold their birthright for a mess of pottage’Footnote 43 inasmuch as they have acquiesced to modernism’s rejection of formal and final causes. Whereas intelligent design theory can only argue for the probability of intelligent agency in nature and must leave the identity of that agency unresolved, the Aristotelian metaphysics of Thomas provides ‘a strict and airtight metaphysical demonstration of the existence of God.’Footnote 44

A number of responses are in order. First, the suggestion that intelligent design theorists do not take the existence of final and formal causes seriously seems mistaken. Their emphasis on information as being as necessary to explain biological life as matter and energy, and their insistence that such information cannot be derived from matter and energy, belies such a claim. They are quite willing to maintain that what makes the matter making up a rabbit a rabbit, as opposed to, say, a partridge is the form imposed by the information residing in its DNA.

Second, to affirm the existence of formal and final causes in the material world does not preclude raising the question of whether the natural order can, or did, give rise to living beings without intervention by intelligent agency. One can affirm the cosmological insight that even if the universe consisted of one electron that electron would have teleology and would require God to sustain its existence.Footnote 45 Such a universe, however, excludes biological life. The issue is not whether any world at all requires God for it to be, but rather whether that order was intervened upon by intelligent agency in the production of living beings. As Lydia McGrew comments,

when someone promoting an ID argument says that it is probable that such-and-such a particular phenomenon…was the result of intelligent design, he need not be saying that the cosmological argument…doesn't work, that God isn't a necessary being, that it is not the case that everything in the universe depends on God for its existence, that God doesn't sustain the whole world, that God didn't create the whole universe…What he is saying is that it is probable that this particular phenomenon (not everything in the universe indiscriminately) was the result of special agent intention. And special agent intention just isn't what we mean by any of those other things. It isn't included in God's sustaining the universe or God's being the Ultimate Cause… ID arguments proceed from particular noticed facts and the explanation of special intention for those particular facts.Footnote 46

Third, Feser’s denial of any genuine analogy between human artifacts and biological entities is problematic. By way of example, he contrasts a watch, as a human artifact, and a human heart, as a material substance. He asserts that the parts of the watch ‘have no inherent tendency to perform the function of telling time…and must be forced to do so by an outside designer [but] that a heart has the function of pumping blood is something true of it simply by virtue of being the kind of material substance it is.’Footnote 47 In his view, there is

a fundamental metaphysical difference between natural substances and human artifacts. The parts of a living thing…are oriented inherently and by nature toward functioning together for the good of the whole. The parts of an artifact, by contrast, have no inherent or natural tendency to function together in this way, and must be made to do so by something outside them. Their natural orientation is toward different ends – those inherent in their being whatever natural substances they have to be – even if an artificer might be able to organize them in such a way that these natural tendencies do not frustrate the artificial end he wants them to serve....artifacts and the ends they are made to serve presuppose non-natural substances and the tendencies they naturally exhibit, so that it is incoherent to model natural substances on artifacts.Footnote 48

It is far from clear, however, that affirming the existence of formal and final causality requires maintaining that there exists no genuine resemblance between living beings and human artifacts. Living beings and human artifacts operate on the same physical principles, and both have internal structures that, arguably, cannot be entirely accounted for in terms of the causal powers of their constituent parts. It is true that living beings, though not constituent organs such as hearts, reproduce themselves, whereas human artifacts do not, but that will hardly suffice to draw the metaphysical distinction Feser wants to put in place, since it is possible in principle to design and build a sophisticated machine or system capable of reproducing itself.Footnote 49

The real question is not, as Feser would have it, whether there exist in the natural world final and formal causes and thus real essences, but, as has been noted, whether the natural order inherent in inorganic substances can, or did, give rise to living beings, without intervention by intelligent agency. That question cannot be settled merely by arguing for the existence of final and formal causes.

Feser’s claim that God cannot ever be taken as creating ‘in the way a craftsman arranges parts so as to produce an artifact,’Footnote 50 is taken by him to be a logical consequence of maintaining a fundamental metaphysical distinction between living beings and human artifacts. Given that such a distinction is problematic, he provides no genuine grounds for dismissing the suggestion that God’s agency in creation may at least in certain instances be analogous to how a craftsman arranges parts. Certainly, it bears observation that Feser’s insistence that it is logically incoherent to claim a genuine analogy between artifacts and living entities is at odds with Thomas’s willingness to employ such an analogy. Thus, amongst other examples previously cited, we find Thomas asserting that

all creatures are related to God as art products are to an artist,…Consequently, the whole of nature is like an artifact of the divine artistic mind. But it is not contrary to the essential character of an artist if he should work in a different way on his product, even after he has given it its first form. Neither, then, is it against nature if God does something to natural things in a different way from that to which the course of nature is accustomed.Footnote 51

It appears, therefore, that the dismissal of the intelligent design movement by many contemporary Thomists as incompatible with central elements of Thomas’s thought is unjustified. Intelligent design theory is consistent with affirming the complete dependence of all contingent being upon God and the existence of formal and final causes. In taking seriously gaps in purely natural explanations of living organisms, it does not commit the fallacy of argumentum ad ignorantium and, to the degree that it does not see the origin and development of living entities as simply implicit in the nature of non-organic substances, it is in agreement with views explicitly stated by Thomas.