Have Christian theologians reconciled determinism and freedom of the will in spite of the sciences? — UCL Science and Religion (2017)

Science and Religion Have More In Common Than It Might Appear

The issue of free will and determinism is a longstanding theological, philosophical and scientific problem that has been debated vehemently for centuries. The focus of this essay is to examine whether the accounts of compatibilism presented by Thomas Aquinas (1225–1274) and Rene Descartes (1596–1650) reconcile determinism and free will in spite of the modern scientific view that largely accepts determinism but casts doubt on the notion of free will. I will trace the specific socio-historical contexts that defined the debates surrounding compatibilism at the time of Aquinas and Descartes and continue to shape modern theological, philosophical and scientific approaches to compatibilism.

I grant that Aquinas and Descartes present a plausible theological and philosophical account of compatibilism, which is the view that free will is compatible with determinism and my essay calls for a reassessment of the existing literature. I accept determinism in one sense as a reality, but argue for its compatibility with free will, which has many dimensions. I shall first state the problem of the essay, and outline the main theological arguments that attempt to deal with it. I shall consider the theological arguments for compatibilism put forward by Aquinas and Descartes in some detail; which I maintain are plausible, then I will consider some of the criticisms of compatibilism with reference to B.F. Skinner’s Beyond Freedom and Dignity (1971).

Giving a full defence of Aquinas and Descartes’ views against that of Skinner is beyond the scope of this paper; my intention here is simply to determine exactly what Aquinas and Descartes have argued in their accounts and possibly would argue in response to some of the criticisms raised by Skinner.

Before I begin the substantive body of my essay, I would like to define the problem of compatibilism and trace the historical roots of the debate. Firstly, the problem of compatibilism can be formulated as such:

Premise 1: If God knows what I shall do tomorrow, given that God‘s knowledge is infallible, I cannot do otherwise than He foreknows.

Premise 2: It is a matter of necessity that I do what God foreknows.

Premise 3: Something done by necessity is not done freely.

Conclusion: My choices cannot be free if they are all foreknown by God.

As evidenced in the formulation above, the two doctrines in Christian theology that threaten our notion of compatibilism and possibly lead to theological fatalism are (1) the doctrine of infallible divine foreknowledge posited in Premise 1 and; (2) the doctrine of divine providence posited in Premises 2 and 3 (Rogers, 2008, p146). According to Rogers (2008), foreknowledge entails fatalism because if God knows the entire future in a way that cannot be mistaken, then it would appear as if nothing can happen differently. If so, and if human freedom requires the ability to do otherwise, it appears that we lack free will. Divine providence threatens fatalism because if everything occurs under the ordinance of God’s will, then apparently everything happens the way God determines it, which again suggests that we lack the power to act differently and are not free.

Secondly, the term ‘free will’ or liberum arbitrium comes out of early Christian theology and was used to help explicate the underlying reasons that motivate humans to act in a way consistent with God’s plan or commit sin (VanArragon, 2010, p21). Also, ‘Christianity’ is a broad concept that cannot be neatly corralled into one category. The focus of this essay, however, will be on the Catholic approach to compatibilism principally since both Aquinas and Descartes operated under this dominant branch of Christianity and presented lengthy accounts in support of compatibilism (Conway, 1911; Rodis-Lewis, 1999, p97).

Further, I have chosen to pay special attention to Aquinas and Descartes as it is agreed among historians that Aquinas was one of the two most influential Christian philosophers, along with St. Augustine (354–430) (Hartung, 2013, p1) and Descartes’ famous account of the mind-body dualism, which he puts forward in the Meditations and Principles is viewed by many theologians as a plausible solution for compatibilism. According to Descartes, the physical world could be construed as a deterministic ‘machine’ composed of matter and natural laws, but the ideas and thoughts of humankind are in fact free (Hartfield, 2014).

Although it might be argued that Aquinas and Descartes’ theologies do not necessarily reflect all of Christianity as a coherent whole, I contend that Aquinas and Descartes’ arguments in support of compatibilism have heavily influenced Christian views on free will and determinism (Hartung, 2013; Hartfield, 2014). Moreover, their accounts continue to be invoked by contemporary writers on the subject, which suggests that there is sufficient merit to their views worth further examination (Kane, 2005; Zagzebski, 2005).

Firstly, let us consider Aquinas’ strongest claim for compatibilism, which is that God’s foreknowledge is the cause of all things, including the free will of human beings. Aquinas argued that although God can be said to have knowledge of what is to come, His knowledge of the future does not necessitate our actions and therefore does not prevent us from being free (Hartung, 2013, p76). To support this point, I will make references to two passages of the bible that likely would have influenced Aquinas’ view. It is important to note that there are multiple levels of interpreting the bible: literal, moral, allegorical/spiritual and anagogical, and Christian theologians often disagree on the hermeneutics (Encyclopædia Britannica, 2010). For the purposes of this essay, I will offer my own interpretation of the scriptures based on how I imagine Aquinas and Descartes’ would argue but the reader is welcome to disagree with my views:

‘And those he predestined, he also called; those he called, he also


Romans 8.28–9

‘I have set before you today life and good, death and evil, in that I command you today to love the Lord.’

Deuteronomy 30:15

In the first passage, the bible clearly suggests that, in one sense, determinism exists in the form of ‘predestination’, which is the doctrine that God has ordained all future events. The accounts of predestination presented by Aquinas, St Augustine of Hippo, Martin Luther (1483–1546) and John Calvin (1509–1564) support a strong form of predestination, which suggests that God predestines who will go to heaven and who will go to hell by virtue of His infinite grace or ‘omnipotent providence’ (Hartung, 2013, p43; American Heritage Dictionary, 2011). Where Aquinas differs is to say that predestination is not equivalent to divine foreknowledge and he maintains that there is a causal relation between predestination and salvation (Hartung, 2013, p81).

I admit that it is not entirely clear what Aquinas means here but I suppose it is possible that God can predestine some to go to heaven without necessitating it in the same way that Aquinas grants that God permits the existence of evil without necessitating humans to be evil: a point I will return to later. In the second passage, the bible suggests that while the paths of ‘life and good’ (heaven) and ‘death and evil’ (hell) precede the existence of humanity, it is up to humanity to ‘obey’ God’s ‘command’ (Deuteronomy 30:10,15), which supports Aquinas’ view that determinism can be reconciled with free will without entailing fatalism.

The counterclaim is that if God’s foreknowledge is the cause of all things, then God is responsible for human evil. Isaiah 45:7 is one verse of the bible that is often cited as evidence that God explicitly creates ‘darkness’ and ‘calamity’ (evil) alongside ‘light’ and ‘peace’ (good), and critics hold that compatibilism cannot be true if God, not humans, is to blame for the evils of our world. However, this counterclaim fails and Aquinas explicitly rejects this view in two ways.

Firstly, Aquinas’ rejoins that evil is not in and of itself knowable in the relevant sense and that since evil is the ‘privation of good’, God knows evil by reverse engineering, that is, by the very fact that He knows good things, He knows evil things (Hartung, 2013, p71). In other words, if one is to have unlimited faith in the omnibenevolence of God, which I grant Aquinas does, one would argue that evil exists because it is the absence or privation of good, and since it is logically impossible to have a concept of good without evil, God’s knowledge of logical opposites means that He is forced to tolerate the existence of evil (but does not Himself orchestrate evil) as a way to preserve our free will. Moreover, I would argue that if God did not permit evil to exist, humans would act in a good manner out of necessity and not by choice, and if by necessity, we would not be acting freely. The existence of evil is, therefore, strong evidence of compatibilism.

Secondly, Aquinas would respond to this counterclaim by invoking the doctrine of timelessness. According to Aquinas, God is not conformed to the linear ‘temporal order’ to which we as humans are confined (Hartung, 2013, 72), which is supported by 2 Peter 3:8 that states ‘with the Lord a day is like a thousand years, and a thousand years are like a day.’ Aquinas’ rejection of Premise 1 from the classic formulation of compatibilism is rooted in his posit that God does not exist in time as we conceive, and this remains one of the most respected solutions to the dilemma of theological fatalism to the extent that modern writers continue to defend this view (Zagzebski, 2005).

We have just seen how Aquinas would defend compatibilism. I will now present Descartes’ main arguments in support of compatibilism.

Firstly, Descartes most powerful argument in support of compatibilism is the very fact of doubting is, in his view, an act of free will. As I alluded to earlier, Descartes is deterministic about the natural world but maintains that we have free will. In Meditations II Descartes describes his method of moving from ‘hyperbolic’ or ‘radical doubt’ to absolute certainty about what is knowable in a neatly expressed line of reasoning: ‘cogito ergo sum’, which translate to ‘I think, therefore I am’ (Hatfield, 2014; Skirry, 2017). This foundational argument was later revised by Antoine Léonard Thomas (1732–1785), in an award-winning 1765 essay to ‘I doubt, therefore I think, therefore I am’ and I think this is better captures Descartes’ central thesis which is that one’s ability to doubt is proof of one’s existence and that one possesses ‘wilful mind’ (Hartfield, 2014).

Descartes accepts that there are fixed laws that govern nature and that humans are usually compelled to trust what we perceive even if our sensory judgments turn out to be false. However, he maintains that our mental faculties are pro tanto undetermined and that the ‘rational mind’ is thus both ‘free’ and ‘constrained’ since God has given us a will that is ‘intrinsically drawn to the good’ (Hatfield, 2014; Ragland, 2016, p6, 137–140). Further, Descartes endorses The Principle of Alternative Possibilities, that is, the ability to do otherwise, or as Descartes phrases it in Meditations IV: ‘the ability to do or not to do something’ (O’Connor, 2010).

The counterclaim is that the ability to doubt or do otherwise is not evidence of a ‘wilful mind’ but, according to the behavioural psychologist, B.F. Skinner, it is a result of environmental ‘contingencies’ that increase the probability of specific behaviour in an individual (1971, p42). He called this the principle of reinforcement (Schacter, Gilbert & Wegner, 2011, p17). Skinner rejects the notion of free will entirely and in Beyond Freedom and Dignity, he suggests that a scientific analysis of human behaviour transfers all of the control and autonomy that humans purport to have over to the environment (ibid, p200).

One example Skinner cites to support his claim is that of the primate hand which, in his view, has evolved so that it can be better ‘manipulated’ due to the ‘process of [natural] selection’ as opposed to ‘prior design’ (ibid, p199). Skinner then equates this example with that of a pianist who, in his view, does not learn or play a scale because of prior intention, which appeals to the notion of will, but due to ‘reinforcing’ contingencies (ibid, p199). However, this counterclaim fails and a compatibilist would reject Skinner’s argument in several ways.

Firstly, Skinner presents a false analogy here by comparing the primate hand that passively evolved in a Darwinian sense and a pianist who deliberately chooses to play the piano. He fails to recognise these are two distinctly different scenarios that contain important nuances: the former involves a process of change that takes place over geological periods and occurs unconsciously and involuntarily, whereas the latter involves a process of learning and execution that occurs consciously, within the pianist’s lifetime and, arguably, with the pianist’s full consent. This dichotomy can be resolved if we adhere to Descartes’ mind-body dualism.

Further, in other parts of his book, Skinner appears more ambivalent about the relationship humans share with the environment. At one stage, Skinner explicitly states paradoxically that humans are ‘indeed controlled by [our] environment’ but that it is ‘an environment largely of [our] own making’ (1971, p201). Just which takes precedence, the environment or humanity? The latter half of his statement would support the compatibilist instinct that there is a balance between human autonomy and environmental determinism but to suggest humans are ‘controlled’ by the environment, which he asserts in the former half of the sentence, ignores the reality that we possess the ability to customise our environment in accordance with our will even when the environment resists. The fact that humans have conquered inhabitable parts of the world, for example, is evidence humanity’s ability to have, in a theological sense, ‘dominion’ over our environment (Genesis 1:26), which Skinner fails to refute.

Another way Skinner might respond to this is by accepting that humans as a species can exert influence over the environment while maintaining that individual autonomy is a myth since, in his view, an individual is ‘merely a stage in a process which began long before he came into existence and will long outlast him’ (ibid, p204). However, this argument fails too because one cannot make sense of the achievements made by humans as a species without taking into account the contributions made by individuals. To defend his view, Skinner would have to justify why any given event in history resulted the way it did without committing weak regress arguments and engaging in fallible counterfactuals to decide whether the environment mattered more than the individuals in question. But I cannot see how Skinner could do this without appealing to the notion of individual autonomy and rationality.

In conclusion, I have argued in favour of compatibilism. By examining Aquinas’ argument for the non-necessity of God’s divine foreknowledge and the Cartesian method of doubt and mind-body dualism, we are able to see how Christian theologians can reconcile free will and theological determinism.

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