Critically compare the cosmological and teleological arguments for God’s existence. [40]

St Thomas Aquinas presents five ways of demonstrating God’s existence based on observation in his Summa Theologica (1,2,3).  The first four of these ways are Cosmological arguments, reasoning from observations of movement, efficient causation, contingency and grades of perfection in the universe a posteriori to the conclusion that God as a Prime Mover, uncaused cause, necessary being and supreme perfection must exist.  The fifth way is a teleological argument, reasoning from observation of order and purpose (teleology) in the universe a posteriori to the existence of an intelligent designer “which is what everybody calls God.”  Clearly, Aquinas saw both Cosmological and Teleological Arguments as persuasive arguments for God’s existence, however the Teleological Argument offers better support to the God of Christian worship than the Cosmological Argument does.

David Hume criticised cosmological arguments in his Dialogues Concerning Natural Religion (1779).  His character Philo pointed out that it is based on limited observations of the universe.  For all we know there might be uncaused things out there… as indeed Quantum Physics and Particle Physics has since shown to be the case.  Further, the argument is based on the fallacy of composition, the assumption that just because the parts of the universe have a cause that the whole universe must have a cause.  As Bertrand Russell later pointed out; just because all men have mothers doesn’t mean that the human race has a mother, it could be that the universe is a “brute fact”.  Hume’s criticisms of the cosmological argument are difficult to overcome.  While it is fair to say that Hume’s claims about the limitations of human observations as the basis for knowledge about natural laws are just as much of a problem for science as they are for religion, his other criticisms hit hard.  In truth, the universe might, for all we know, be uncaused or be its own cause.  It is fair to ask why what is true of the part should also have to be true of the whole.  Although William Lane Craig argues that the cosmological argument – at least in his own Kalam version, which stops short of concluding that the Prime Mover is “what everybody calls God” – is the best support for the reasonableness of faith, his claims about the impossibility of an actual infinite and about the Big Bang theory needing a cause have been shown to be mistaken by critics such as Erik Sotnak and Stephen Hawking.  While the cosmological argument might superficially seem to be supported by Big Bang theory, in reality Cosmology shows that the idea of causation cannot apply outside the space-time matrix of our universe.  While it seems incredible, as Terry Pratchett quipped, science proposes that “in the beginning there was nothing, which exploded.” It is clear, therefore, that the cosmological argument is not persuasive. 

Hume’s character Philo also attacked the teleological argument in the Dialogues, criticising the tendency to make the argument using inappropriate analogies and pointing out apparent imperfections in the design of the universe, which might undermine the idea that the designer would be perfect.  Later, both Charles Darwin and JS Mill pointed out the brutality in nature and reasoning that an Ichneumon wasp could not have been designed by the God of Christianity.

Nearly all the things which men are hanged or imprisoned for doing to one another are nature’s everyday performances.”  Mill: Three Essays on Religion

Nevertheless, these critics all failed to exclude the possibility that the universe could be designed to contain evil for some morally sufficient reason.  As St. Augustine argued, it could be that natural evil in the world is a just punishment for sin.  Moral evil could be the necessary bi-product of human freedom.  Evil does not necessarily undermine the claim that the universe was designed by God.  Alternatively, as John Hick argued, suffering could be positively created by God to afford the opportunity for “soul-making” with any injustices being accounted for through an afterlife.  Further, there are versions of the teleological argument which do not rely on spurious analogies – such as FR Tennant’s aesthetic argument and anthropic principle.  These are more persuasive than the cosmological argument.  Hume’s criticisms fall short of undermining Tennant’s claim that God is needed to explain beauty and human consciousness in the universe and evolution through natural selection fails to explain these aspects of the universe adequately either.  Modern Intelligent Design arguments – such as those proposed by Michael Behe from irreducible complexity and by William Dembski from specified complexity – show that evolution cannot provide the complete explanation that atheists like Richard Dawkins claim it can.  While Paley’s argument in Natural Theology can be rightly criticised for its use of the famous watchmaker analogy, its appeal to our incredulity at the scientific claim that all this could have arisen by chance is powerful.  To accept that evolution through natural selection can provide a complete explanation of the universe and that there is no intelligence guiding it is difficult to accept.  Take the Japanese puffer-fish… can evolution really account for the extent of the intricacy and beauty of its designs?  It is clear, therefore, that the teleological argument is more persuasive than the cosmological argument.

In addition, even if the cosmological argument was persuasive, it would only serve to demonstrate the existence of a Prime Mover, an uncaused cause, a necessary being outside time and space.  It is not easy to see how this being could be the God of Christian worship.  Aristotle stopped short of claiming that the Prime Mover could be a God in any normal sense, its power being limited to supporting the existence of all contingent things and its goodness being limited to being fully actualised and containing no potential. How could a God who is outside time and space act to create the universe when there could be no time before during or after his action and when there would be no space to differentiate the creation from the creator?  Both human understanding and the language which tries to communicate it struggles to cope with objects outside the space-time matrix which bounds our experience.  It might, of course, be fair to say that human understanding and language cannot expect to be able to comprehend or describe God.  Yet, without the ability to claim that God exists, that God is the all-powerful creator and that God is good with some content, it is difficult to see how Religion could prosper.  St. Thomas Aquinas attempted to show how human language could be used to describe God in positive terms as analogies, but even he admitted that he content of attributes such as goodness must needs be limited and cannot be understood in the same way as human goodness.  The teleological argument, by contrast, does not rely on locating God outside time and space.  As the intelligent designer, it seems likely that God would have defined the purpose of the universe from within the same logical framework which governs its operation today.  In this way, God’s power and goodness have real content, as they relate to how He created the complex order and purposiveness we can observe.  It follows that the teleological argument offers better support for the God of Christian worship than the cosmological argument does.

In conclusion, the teleological argument offers better support for the God of Christian worship than the cosmological argument does.  Clearly, the teleological argument relies on the possibility of defending God’s goodness and power against charges of creating or allowing evil and suffering, but it is still more persuasive than the cosmological argument.  Even Immanuel Kant, who rejected all the classical arguments for God’s existence in his Critique of Pure Reason, saw the age and persistence of the teleological argument as pointers to its status as the most powerful of the arguments for God’s existence.

Critically assess the claim that human beings have an immortal soul. (40)

The claim that human beings have an immoral soul is certainly ancient.  It is clear that Plato’s dualism was built on the foundation of Socrates’ belief in immortality and possibly reincarnation.  In addition, evidence from the Bible suggests that belief in an immortal soul predated Christianity – though the belief is not represented consistently in the Old Testament – and became increasingly important as hopes for an immanent eschaton faded with the 1st Century. Further, the idea that personal identity can survive trauma, aging and ultimately death fits with human experience and supports both morality and hopes for life after death which many of us want if not need to maintain.  Nevertheless, despite the persistence and appeal of these beliefs, claims that human beings have immortal souls lack credibility in the 21st Century.

Firstly, as Aristotle observed, “the soul is inseparable from its body” [On the Soul, Book II] He used the analogy of wax and a seal impression to make his point, writing “we must no more ask whether the soul and body are one than ask whether the wax and the figure impressed on it are one.” [Aristotle “Psychology” translated by E. Wallace, p. 61, 1882]  While he accepted that human beings have PSYCHE, and that these come in three parts, unlike his teacher Plato, Aristotle rejected the idea that this could ever be separated from the body or survive death.  As Brian Davies OP has noted, just because I consider myself to be sober doesn’t mean that I am. The fact that I feel separated from my body doesn’t mean that I am.  GEM Anscombe agreed, arguing that the feeling of having a separate soul is not a proper argument for the soul’s separability.  Further, as Gilbert Ryle suggested, the soul is the product of the parts and functions of the body operating together.  When we speak of “the soul” it is much like speaking of “the university” in Oxford or “team spirit” in cricket… these things are an undoubtedly part of our experience, but they cannot be separated from the components which make them up.  As Ryle wrote in “The Concept of Mind” (1949) Chapter 1, belief in a separate, separable and possibly immortal soul is the result of “that a family of radical category mistakes”… continuing, this “is the source of the double-life theory. The representation of a person as a ghost mysteriously ensconced in a machine derives from this argument”. To claim that human beings have separable souls, which – not least given our certain scientific knowledge that bodies decompose – is a precondition of having immortal souls, is to build assumptions on top of gut feelings in spite of the evidence, to make a “category mistake” and to take what is essentially a metaphor literally.  

Secondly, as Richard Dawkins has argued, the theory of evolution can account for the impression of consciousness which contributes to the claim that human beings have immortal souls.  In The Selfish Gene (1976) he wrote “we are survival machines – robot vehicles blindly programmed to preserve the selfish molecules known as genes.” In 1993 he speculated that the impression of consciousness and a separate soul has become an essential part of being human because it confers a survival advantage to our genes, suggesting that “brain hardware has co-evolved with the internal virtual worlds that it creates. This can be called hardware-software co-evolution.” The Evolutionary Future of Man (1993)  Dawkins’ reductive materialism is supported by the famous case of Phineas Gage, who suffered a traumatic brain injury and then experienced a complete transformation of personality and identity as a result.  The mind, consciousness or “soul” is nothing more than the impression given off by the normal operation of the brain.  Change the brain, change the “soul”.  Kill the brain, destroy the soul.  Basic biology shows that the soul is far from being immortal and that any claim that human beings have an immortal soul lacks credibility in the 21st Century. 

Further, Peter Geach agreed with the evolution argument, arguing that human beings are sophisticated animals and that our belief that we are somehow different is no more than “savage superstition” [God and the Soul (1969),quoted by John Haldane in Anscombe and Geach on Mind and Soul (2016)].  It is undoubtedly convenient that human beings claim to have a “soul” where other – genetically similar – animals do not.  For Christians, the existence of the soul explains the unique connection between human beings and God, in whose Image they are made.  Further, the existence of a soul both justifies our preferring members of the species homo sapiens in moral decision-making and supports the religious principle of the Sanctity of Human Life.  If human beings have no separable soul or any claim to immortality then it becomes more difficult to justify decisions which ignore the claim of tribes of orangutans on Indonesian rainforests or which deprive blue whales of their habitats for the benefit of a few human capitalists with financial interests in palm oil or Krill.  As far back as the 18th Century Immanuel Kant highlighted the importance of believing in immortality for moral philosophy.  As he argued, without believing in God, freedom and immortality it would be impossible to explain our duty to follow the moral law as there would be no reason to suppose that the law which appeals to us has authority, that we have the ability to do what we feel called to do or that there could be any ultimate point in doing so.  Without the possibility of immortality, which the separable soul supports, there is little reason to do what is right in a world where goodness is rarely rewarded in this life.  Nevertheless, the undesirability of the alternative conclusion is not a proper argument for the existence of an immortal soul in human beings, so the claim that human beings have an immortal soul lacks credibility.  

Clearly, there are arguments in favour of dualism.

Plato used his famous slave-boy in the Meno to argue that we have memories of the forms, either from past lives or from our soul’s previous home in the world of the forms, which best explain our ability to “learn” mathematics and logic quickly.  For Plato, learning is really remembering.  Today, Noam Chomsky’s work on language acquisition makes this idea more interesting  than it might have seemed a few decades ago, however even nativist accounts of language and research evidence indicating that the human brain is somehow “hardwired for language” does not take away from the possibility that this hard wiring could be explained by evolution, without the need to hypothesize the existence of an immortal soul.  

In addition, Descartes built on Plato’s scepticism about sense-data, pointing out the many ways in which the evidence of eyes and ears turns out to be mistaken.  A stick put in water surely does appear to bend.  Nevertheless, Descartes’ radical conclusion, that the only thing of which I can be certain is “cogito ergo sum” seems to go well beyond the evidence.  In 1968 Norman Malcolm poked holes in Descartes reasoning on a technical level, however even in the most obvious way it is apparent that while the senses do lie, conceptual analysis just as often deceives us.  As Aristotle himself pointed out, “if, then, a man has the theory without the experience, and recognizes the universal but does not know the individual included in this, he will often fail…” [Metaphysics Book 1:1]  Further, Descartes’ arguments for substance dualism, with the seat of the soul in the Pineal Gland, can only in the light of 21st Century science, be seen as uninformed speculation.  Descartes is far from being justified in his conclusion that “it is certain that I am really distinct from my body and can exist without it.” [Meditations Book VI, 54] and the claim that human beings have an immortal soul continues to lack credibility.  

Finally, paranormal experiences and particularly Near Death Experiences have been used to support claims that human beings have immortal souls.  For example, in 1991 American singer-songwriter Pam Reynolds had a powerful experience of being separated from and looking down on her body and of spending time in “heaven” during a stand-still operation for a brain aneurism.  Nevertheless, most of these experiences fail to stand up to careful scrutiny.  Susan Blackmore described her own journey to this realisation, writing

It was just over thirty years ago that I had the dramatic out-of-body experience that convinced me of the reality of psychic phenomena and launched me on a crusade to show those closed-minded scientists that consciousness could reach beyond the body and that death was not the end. Just a few years of careful experiments changed all that. I found no psychic phenomena—only wishful thinking, self-deception, experimental error and, occasionally, fraud. I became a sceptic” The New Scientist (2000)

Further, those experiences which resist explanation in simple physiological or psychological terms, such as those highlighted by Dr Sam Parnia in his Aware and Aware II studies, are few in number and may still be explained by scientific progress.  Just because we cannot explain a few experiences with current scientific models doesn’t give us a reason to ditch scientific materialism and regress to a primitive dualistic world view predicated on supernatural entities for which there is no evidence.  

In conclusion, the claim that human beings have immortal souls lacks credibility in the 21st Century.  While the claim speaks to the experience of being human and supports the convenient belief that human beings are ontologically different from animals, there is no proper evidence or sensible argument to support substance dualism.  Those with religious faith will, of course, continue to make the claim that human beings have immortal souls.  The claim is central to their world-view and it is difficult to imagine how Christianity in particular could function without it.  Yet in making the claim believers emphasize how far in faith they are willing to stray from what can be supported through evidence and argument.


  • Class Notes on Soul, Mind & Body
  • Gilbert Ryle “The Concept of Mind” Chapter 1
  • Susan Blackmore “Consciousness: An Introduction”

“Aquinas’ Cosmological Argument proves that God exists.” Critically evaluate this statement.  [40] 

Cosmological Arguments start with the existence of the universe (Greek = Kosmos) and conclude that God is the most logical explanation of it.  They are some of the oldest arguments for God’s existence and have an intuitive appeal.  As Richard Swinburne observed in “Is There a God?” (1996)

The human quest for explanation inevitably and rightly seeks for the ultimate explanation of everything observable.”

Cosmological Arguments can be found in the work of Plato (Laws Book X) and Aristotle (Physics Book II, Metaphysics Book IV) and make up the first four of Aquinas’ five ways to God in the Summa Theologica (1.2.3).   While Aquinas’ Cosmological Arguments are all framed as posteriori arguments – and so could never provide proof – they do provide strong support for the existence of a Prime Mover.  Nevertheless, Aquinas goes too far in his claim that this is what everybody calls God.

Aquinas’ first way draws on the Aristotelian concept of movement. In the Physics, Book V, Aristotle wrote, “all things that are in motion must be moved by something.”  Motion does not necessarily mean movement in the sense that things are is moving through space from location A to location B, but rather that they are moving from a state of potentiality to a state of actuality in multiple different respects. As Aristotle wrote, movement involves the… “actualizing of some potency. It is because things have real potencies that they are able to change.”  Aquinas later wrote, “for motion is nothing else than the reduction of something from potentiality to actuality.”  Whereas Plato’s argument, later refined by Muslim scholars of the 8th Century Kalam School and more recently by William Lane Craig, focuses on a temporal series of causes much like a domino-rally, pointing towards a beginning in time, an uncaused cause, which is what everybody calls God, for Aristotle and for Aquinas, even if the universe is as infinite as it appeared to be, there is still the need for a Prime Mover because everything depends on other things.  As Parmenides, Heraclitus and separately the Buddha observed, everything changes or moves and nothing stays the same, but nothing changes or moves without being moved by something else, even if that is just time itself.  As Aristotle wrote, “potential, precisely because it is potential, cannot make itself actual”.  Aristotle concluded that there must be a Prime Mover outside time and space, but stops short of claiming that this is God.  Aquinas went further, claiming that this Prime Mover is “what everybody calls God”, but in doing this he weakened the argument. It is true that the Prime Mover must be outside time and space and thus wholly simple and unchanging, pure actuality and with zero potentiality.  As Aquinas wrote,

“nothing can be reduced from potentiality to actuality, except by something in a state of actuality… it is impossible that in the same respect and in the same way a thing should be both mover and moved…” 

It is also true that everything ultimately depends on the Prime Mover for its existence.  As Aquinas wrote, “therefore it is necessary to arrive at a first mover, put in motion by no other”  However, it is a step too far to claim that the Prime Mover could be seen as the “creator”, let alone act in the world, speak to human beings or be crucified and rise again. When Aquinas writes “and this everyone understands to be God”  He goes beyond the evidence and possible knowledge.  In his book “The Nature of God” Gerard J. Hughes describes the Prime Mover changing potentiality to actuality in terms of a bowl of milk causing a cat to cross a room.  The bowl of milk does nothing, in the way that the Prime Mover – being timelessly unchanging and impassive – does nothing, because it has no potential and is pure act. It follows that Aquinas’ first framing of the Cosmological Argument provides strong support for the existence of a Prime Mover, but not for the existence of the God that Christians worship, because the Prime Mover would be unable to say “let there be light”, work miracles or judge individuals on the final day… all of these require in God potential and the ability to act in time, which the Prime Mover cannot have.

Aquinas’ second way draws on the Aristotelian concept of efficient causation.  For Aristotle, all things have four causes – material, formal, efficient and final.  Efficient causes are agents which bring things into being, in the way that parents bring their children into being or the earth, sun and rain bring the oak tree out of the acorn.  If everything depends on efficient causes to bring them into being, again there is a chain of causation which requires explanation.  The chain cannot be infinite, because if there was no first efficient cause there would be no subsequent causes and the universe would not exist.  Something cannot come out of or be caused by nothing. Similarly, there cannot be a first efficient cause like other things in the universe, as if there were it would need efficient causes of its own and could not, therefore, be the first.  Aquinas concludes, “it is necessary to admit a first efficient cause, to which everyone gives the name of God.” Again, Aquinas’ second Cosmological Argument provides strong support for the existence of an uncaused efficient cause and again, it is a step too far to claim that this must be the God of Christian worship.  This not least because efficient causes do not need to be sustaining causes in esse (as Frederick Copleston later called them) but could be a cause in fieri (again, to use Copleston’s terminology).   An uncaused cause which began the universe but has no further role in it is not the God of Christian theism; at most it supports deism.  Further, Aquinas admits that

There is no case known (neither is it, indeed, possible) in which a thing is found to be the efficient cause of itself; for so it would be PRIOR to itself, which is impossible.”

 This implies that as efficient cause the uncaused cause must be PRIOR to the universe, something which would be difficult to reconcile with Big Bang Theory as this suggests that as time itself was created at the Big Bang, it makes no sense to speak of anything being PRIOR to it or indeed, as Stephen Hawking observed, causing it.  In these ways, Aquinas goes beyond the evidence in claiming that the uncaused cause is that to “everyone gives the name of God”.

Aquinas’ third way develops the idea of the contingency of things in the universe, pointing out that everthing has the potential to be or not to be; “We find in nature things that are possible to be and not to be”.  In an infinite universe, all potentials not to be might be expected to have been realized; as something can’t come out of nothing, nothing would then exist and I could not be writing this essay.  It follows, therefore, that EITHER the universe cannot be infinite – in which case there would have to be a first cause in time which would be what everybody calls God – or the universe is infinite and there exists a “necessary being”, a fully actual “neither something nor nothing” which contains its own explanation and has no potential not to exist.  This, Aquinas claims, is what “all men speak of as God.”  Aquinas’ third Cosmological Argument is just as problematic as an argument for the existence of the God of Christian worship as the first and second.  Not only as an a posteriori argument does it stop short of providing proof, it also goes well beyond the observable evidence in concluding that the necessary being is God as Christians would define Him.  Leibniz later recast the third Cosmological Argument as an a priori argument, writing:

“Why is there something rather than nothing? The sufficient reason […] is found in a substance which […] is a necessary being bearing the reason for its existence within itself.” 

For Leibniz, anything that exists has a cause for its existence, either in the necessity of its own nature or in an external cause.  If the universe has an external cause for its existence, this cause must be God.  As the universe exists, it must have a cause for its existence, either in the necessity of its own nature or in an external cause.  Because the universe exists contingently, not necessarily, the universe must have an external cause and this must be God.  Nevertheless, like Aquinas, Leibniz argument fails to prove the existence of the God of Christian worship.  Causing the universe is not enough to be called God; the Christian God does rather more than an abstract singularity or the Higgs Boson does.  Further, it doesn’t make sense to predicate much of what the Christian God does to the necessary cause of the universe supported by Aquinas and by Leibniz in his supposed improvement of Aquinas’ third cosmological argument.  Both the God of Aquinas and the God of Leibniz are timelessly impassive and it is inconceivable how such a being could act even once to create the world, given that this would involve a change in its being incompatible with being timeless and fully actual with no potential.  Further, as Immanuel Kant observed, we have no experience of necessary beings so it makes little sense to speculate about their possible existence.  Also, it is inconsistent to start an argument by claiming that all things are contingent and conclude by hypothesizing something that is not contingent.  Again, while Aquinas’ third Cosmological Argument strongly points towards the existence of a necessary being or beings in the universe, it is far from being conclusive proof of such, even when recast as an a priori argument and cannot in any case justifiably claim that the necessary being is what Christians worship as God.

While it is true that most of the classical criticisms of Aquinas presented by David Hume and Bertrand Russell fail to undermine his Cosmological Arguments, the point (which they all make) about the Cosmological Argument failing to support the God of Christian worship stands.

Firstly, Hume criticized a version of the Cosmological Argument presented by his character Demea in Dialogues Concerning Natural Religion (1779) Book IX.  Cleanthes points out that there is no support for the claim that everything in the universe is moves and is moved, caused and is caused or is contingent.  We have a limited view of the universe and no sensible reason to believe that the universe is homogenous or that we see things the way they actually are, a principle known in science as isotropy.  For all we know, argues Cleanthes, there could be unmoved movers, uncaused causes or necessary beings within the universe which could explain its continued existence.  Nevertheless, accepting these criticisms of the Cosmological Argument entails abandoning Natural Science altogether.  Leibniz coined the term “Cosmological Principle” to refer to the principles of homogeneity and isotropy which all scientists must assume in order to reason inductively towards natural laws.  Without the Cosmological Principle, we could not make many scientific knowledge claims; Cosmology and Quantum Science, Medicine and Biochemistry would all be a waste of time.  In practice, laws of nature supported by inductive reasoning enable mobile phones and space shuttles to work, so it doesn’t make sense to doubt the authority of our observations as Hume, through Cleanthes, does.  These criticisms of Hume’s fail to undermine Aquinas’ Cosmological Arguments insofar as they point to a necessary cause for the universe.

Secondly, Cleanthes continues by criticizing the claim that just because the parts of the universe have causes, so must the universe as a whole.  Demea (and Aquinas) rely on the so-called fallacy of composition.   Further, Cleanthes asks why the universe cannot be the explanation of itself, why there must be an external cause for the universe.  Later, Bertrand Russell asked why the universe cannot be a “brute fact”.  Yet neither of these criticisms is conclusive.  As Leibniz points out, it is difficult to see how a universe of contingencies can itself exist necessarily.  Contingencies involve potential which cannot, by definition, exist within a necessary being.  Further, while characteristics of the parts do not necessarily have to be characteristics of the whole and while (as Russell argued) just because all men have mothers it doesn’t mean that the human race has a mother, it can sometimes follow.  Each strand of spaghetti has two ends, something which also applies to the whole packet of spaghetti.  In a sense and because it is made up of material in the way that things in the universe are, the universe is a thing.  Things exist contingently and need to be moved and caused by things other than themselves.  These criticisms of Hume’s fail to undermine Aquinas’ Cosmological Arguments insofar as they point to a necessary cause for the universe as well.

Nevertheless, Cleanthes’ criticism that the cause of the universe could not be said to have the attributes of the Christian God is, for reasons previously explored, is persuasive.  Again it is clear that while Aquinas’ Cosmological Arguments do offer support to the hypothesis that there is an uncaused, necessary cause for the universe, they are far from proving that the God of Christian worship exists. 

In conclusion, Aquinas’ Cosmological fail to prove that God exists, both because as a posteriori arguments they stop short of proving their conclusions and because even if they are reframed into a format which could provide proof, as Leibniz attempted, they demonstrate only the existence of an abstract necessary being far short of having the attributes of the God Christians worship. 



  • Class notes on the Cosmological Argument
  • Aristotle, Physics Book V
  • Aquinas, Summa Theologica 1, 2, 3
  • Hume’s Dialogues Concerning Natural Religion Book IX
  • Vardy & Vardy “God Matters” Chapters 4 & 5

“Plato’s theory of the forms is unconvincing!” Discuss. (40)

For Plato, ultimate reality is metaphysical and exists in the “world of the forms” and that things in this world are merely shadows of the forms.  Most famously, Plato discussed his theory of forms through his Allegory of the Cave in Book VII of the Republic.  Here Plato suggests that the forms are accessible through reason and through the work of those who have managed to escape the “cave” of sense-experience to appreciate the ultimate reality beyond.  While Plato’s central point about ultimate reality being metaphysical is convincing, his lack of any real argument for the forms and the apparent inconsistency of his position on them make Plato’s so-called “theory” of the forms unconvincing. 

Plato is unclear about precisely which forms exist metaphysically.  As Julia Annas observes, “Plato never offers an argument for Forms that would establish them as entities suitable for a theory”[1] Further, Plato discusses the forms is presented in several different dialogues, dating from different times in his long philosophical career.  In Book X of the Republic, Plato implies that there are separate forms for tables, beds etc.  Socrates says to Glaucon: “Whenever a number of individuals have a common name we assume them to also have a corresponding idea or form.  Do you understand me? [I do]  Let us take any common instance; there are beds and tables in the world – plenty of them – are there not? [Yes] But there are only two ideas or forms of them – one of the idea of the bed, the other of a table.”[2] Meanwhile, in Book VI of the Republic, through his Allegory of the Sun, Plato implies that only one form ultimately exists – the Form of the Good – and that our impression that a diversity of things exist is a belief rather than actual knowledge, a result of our ideas being clouded by sense-experiences and so not being clear or distinct.  Here, as Julia Annas explains, “Plato contrasted Forms, which are objects of knowledge, with particular instances of Forms (things that ‘partake in’ Forms), which are objects of belief…” [3] The lack of any explicit argument for the forms and the inconsistency of Plato’s position make Plato’s theory of the forms unconvincing. 

In addition, it is not possible to support Plato’s theory of the forms, however it is presented, through either evidence or argument.  Nothing we can observe supports the existence of “forms” whether separately of beds and tables or indeed of the good.  Plato’s position – and that of modern Platonists who accept his theory of the forms – depends on reason alone.  Plato – through the character of Socrates – argues that the existence of the forms is known a priori, before and even without experience, because their necessary existence is contained within our understanding of all other things.  When we experience a chair, we understand what it is and how to use it because we have an idea of a chair which does not depend on having experienced that or any chair.  This explains why we can see a chair that is different from every other chair we have seen and still understand that it is a chair and how to use it.  We can even make judgments of whether it is a good chair or not and know how to design and make a different sort of chair.  “The maker… makes a bed or makes a table for our use, in accordance with the idea…”[4] Yet what is the difference between this sort of rational argument for ultimate reality in the world of the forms and speculation?  What could count against Plato’s argument for the forms if all experience is discounted?  Today, there is evidence to support Plato’s claim that ultimate reality is metaphysical.  Cosmology shows that neither time nor space are absolutes and Quantum Physics that matter consists only in potentialities.  The claim that “man is the measure of all things” and that the way our five human senses perceive reality is the way it really is, is incredible.  Further, there are alternative evidence-based, scientific explanations for our ability to understand, judge and create variations on what we perceive through the senses which do not rely on postulating a supernatural world of the forms.  For example, Noam Chomsky argues that the human brain is “hard wired” for language and that the forms exist in the structures of the brain and the parameters of human language rather than in some metaphysical world.  When there is no evidence to support the metaphysical existence of the forms and when such convincing scientific explanations are available, the claim that we know the forms a priori cannot be maintained.  Plato’s theory of the forms is not convincing, because it is asserted and assumed rather than systematically and consistently argued for. 

On the other hand, as Julia Annas observes, “Books on Plato often refer to Plato’s “Theory of Forms”, but this has to be handled with caution.  Plato not only has no word for “theory”[5] Perhaps Plato never intended to present the forms as a “theory” and it is consequently unfair to evaluate his work as such.  Further, Plato’s theory of the forms has been enormously influential through history and continues to capture the public imagination through films as varied as The Matrix and Interstellar.  However, neither of these counterclaims serve to make Plato’s forms convincing.  Even if Plato never intended to present a coherent theory, his work has widely been interpreted as doing this and other scholars have more than made up for Plato’s lack of argument. For just one example, Descartes developed Plato’s claim that ultimate reality is metaphysical, supporting this with his famous cogito argument in his “Meditations on First Philosophy”.  Descartes pointed out that the five senses are limited and often present flawed data; the only think that I can know with certainty is that I exist as a thinking being and from this I can establish the certain metaphysical existence of “clear and distinct ideas” very much like Plato’s forms.  However, Descartes’ argument has been widely criticised.  While he establishes that he exists as a thinking being, his arguments for the existence of other clear and distinct ideas such as God is widely deemed to have failed.  Kant said that Descartes so-called Ontological Argument for God was “so much labour and effort lost”[6]  Because of this, Descartes fails to offer Plato’s world-view much support.  In addition, that Plato’s theory has been influential and remains popular suggests nothing about whether it is convincing or not on a philosophical level.  A lot of unconvincing theories are popular and influence society… think carrots helping you see in the dark, spinach making you strong and magic charms getting rid of warts.  None of these “old wives tales” have any scientific basis, and yet many people still believe them and behave accordingly.  That Plato’s theory is influential is a poor reason to find it convincing, on a philosophical level.  

In conclusion, Plato’s theory of the forms is unconvincing.  While his basic point about ultimate reality being metaphysical might well be true and remains influential and popular, he fails to argue for the existence of a “world of the forms” or even to present a coherent picture of the same.

[40 minutes]


  • Class Notes
  • Crash Course video on Descartes
  • Julia Annas “An Introduction to Plato’s Republic” Chapters 9 & 10
  • Plato “The Republic”

[1]  An Introduction to Plato’s Republic p.234

[2] The Republic, Book X

[3] An Introduction to Plato’s Republic p.210

[4] The Republic, Book X

[5] An Introduction to Plato’s Republic p217

[6] Critique of Pure Reason, 1781

Critically compare Plato’s philosophical approach with that of Aristotle. [40]

Plato and Aristotle are usually understood to have completely contrasting philosophical approaches.  Although Plato was Aristotle’s teacher at the Academy in Athens, Aristotle rejected Plato’s focus on metaphysics and reason, choosing instead to explore the limits of Physics and observation.  Clearly, Aristotle’s philosophical approach has more influence today.  While modern science has moved way beyond some of the theories which Aristotle proposed on the basis of observation – such as that the universe is infinite, that birds turn into fish and that men implant a “homonucleid” in a woman’s womb – scientific method still accepts Aristotle’s claim that knowledge must begin with observation and that reason must not stray too far from what can be observed, into the realm of speculation.  Nevertheless, and despite the continued popularity of the naïve materialism that emerged out of Aristotle’s philosophical approach, relatively recent developments in philosophy and science have shown that it is Plato’s philosophical approach which is more compelling.

Aristotle’s philosophical approach was supported by Locke, Hume, Kant & Ayer.  All of these philosophers dismissed Plato’s claim that human beings are born with innate ideas which we “remember” through rational reflection.  Instead, like Aristotle, John Locke argued that human beings are born as tabula rasa – blank slates – and that all our knowledge comes from sense-experience, as processed and interpreted by reason.  Hume essentially agreed, as did Kant – who also limited possible knowledge-claims to the synthetic and the analytic – and later Hume’s biographer AJ Ayer in the 20th Century.  The very idea that human beings could source new knowledge in rational reflection without relying on sense-experience seemed to open the door for unsupported speculation, the opposite of knowledge and probably a barrier to attaining it.  Nevertheless, despite the common-sense appeal of empiricism, it has come under attack from several directions.  Firstly, the idea that the only meaningful knowledge-claims are those which can be verified through sense-experience (or are tautologies) was shown to be narrow and impractical.  Aristotle’s attempt to build out from sense-experience to demonstrate the necessary existence of a Prime Mover and a common human telos in which to ground a universal, absolute system of moral philosophy was widely criticised during the Enlightenment and then into the 20th Century.  Descartes and Berkeley pointed out the problems with relying on sense-experience at all.  The way I see things is not necessarily the way that they are; the senses are limited and frequently faulty. Further, there is no way to prove that the exterior world is real, not a dream-world and permanent; as Descartes pointed out, the only thing that I can know with certainty is cogito ergo sum. David Hume himself pointed out additional assumptions on which Aristotle’s reasoning rests, that our limited observations support universal claims about natural laws and that the impression of order and teleology is not just that, an impression.  Cartesian scepticism, Berkeley’s idealism and even Hume’s epistemology point to the shortcomings of Aristotle’s philosophical approach and Descartes and Berkeley’s arguments at least lend support to Platonic rationalism.

Secondly and despite the “liberalisation of empiricism” to include discussions of topics like history that are only weakly verifiable, the focus on sense-experience as the only source of new knowledge excludes important areas of human discussion – and experience – such as religion and morality.  Further, as erstwhile Logical Positivist Karl Popper pointed out, modern science cannot function under a verificationist approach to knowledge.  For example, quantum particles are changed by the act of observing them, demonstrating that the senses do not offer the transparent window on external reality that Aristotle or later empiricists and positivists claimed. Also, as GE Moore pointed out, there is no way to prove that “this is a hand”… at some point the attempt to describe and communicate about sense-experience relies on concepts and conventions, as Hume previously acknowledged when he pointed out that properties like colour are secondary, not primary qualities and this depend on the way we see things, not the way they really are.  It is true that Popper’s falsificationism does not stray too far from that which can at least in principle be experienced through the senses… and certainly does not seem to offer much support to Plato’s rationalism… but it allows for beliefs to be accepted as knowledge providing that criteria for their falsification are accepted.  In the scientific sense, falsification allows for scientists to speculate about the origins and fundamental nature of the universe and about multiverses – none of which can ever be directly observed – if they define the circumstances under which they would modify or abandon their theories.  In a broader sense, falsification enables people to propose moral laws meaningfully – laws which could never be seen, heard, touched, smelled or tasted – providing that they would be willing to accept falsifying evidence.  Alternative theories of knowledge, such as Quine’s holism, recognise the need to include all of human experience rather than just to focus on sense-experience, seeing mathematics as close to the centre of the “web of human experience”, and as such show that Aristotle’s narrower approach has been superseded.  The general rejection of the Verification Principle and the move to find other approaches to knowledge and meaning in the mid-20th century points to the fact that relying on the empirical senses as the source of all new human knowledge – as Aristotle and the empiricists did – is limiting and leads to an impoverished world-view.

Today, Plato’s is a more convincing as an approach to Philosophy than Aristotle’s, because he recognised that reason offers people a better means of understanding things as they really are… although he probably was too confident about how far this could go.  As Descartes pointed out in the 17th Century, reality goes much deeper than superficial appearances.  This begins with all the assumptions people made for millennia – that the earth is flat, the centre of the universe, orbited by the sun and stars in fixed orbits – and includes assumptions that even scientists still make every day – that matter is real, that the way we see things is the way they are, that this part of the universe is a fair sample of a homogenous whole.  To the sceptic, everything in the world of appearances is open to question and nothing is known for certain.  Nevertheless, starting with the foundational claim that I exist as a thinking being, we can have certain a priori knowledge of mathematics, which does more to explain the reality of the universe than ever can direct observations, as theoretical physicists will confirm.  This shows that Plato’s rationalism is more compelling, because it supports current thinking in Mathematics, Theoretical Physics, Particle Science and Cosmology.

In addition, seeing thought and reason as primary also makes more sense of the broader experience of being human.  Plato’s dualism, his suggestion that soul/mind and physical body are separate and even separable, remains far more popular than Aristotle’s suggestion that the soul and body are one and inseparable.  Despite Aquinas’ attempt to argue that an Aristotelian “soul” could be transferred to a new “heavenly” body in an afterlife, this raises more questions than it solves.  The belief in the afterlife, a belief which is extremely widespread, consistent and persistent and even, as Kant argued, required to explain the freedom we all experience as human beings, is much better supported by Platonic dualism than by Aristotlelian monism.  Most people experience a continuity of personal identity and sense of self from early childhood to death.  If the soul is the “formal cause of the body” and the body changes radically over time then we might expect the soul to change as well… but it is consistent.  Most people would agree that changes to the body – becoming a paraplegic for example – has little or no effect on the soul or sense of self, which we might expect to alter if the soul was just the formal cause of the body as Aristotle proposed.  Clearly, if Aristotle was here to defend himself he might point to the effects of traumatic brain injury or dementia, suggesting personal identity depends on the brain as a physical organ and is in no way separate or separable.  As Gilbert Ryle said, Plato’s talk of souls could rest on a category mistake; the soul could be no more than a “ghost in the machine”.  And yet, to dismiss all the evidence for out-of-body and near-death experiences just because it cannot be empirically verified would be hasty.  Recent medical studies by Dr Sam Parnia (AWARE and AWARE II) suggest that the evidence better supports the brain mediating rather than generating the mind.  To use Plato’s own allegory of the cave, might dismissing reports of a metaphysical reality and attacking those who make them be rather like the prisoners in the cave threatening the one who escaped and returned?  Are we satisfied to stay chained in the shadows, blocking out any evidence that could expand our world-view, or are we brave enough to contemplate the possibility of a bigger reality beyond? Plato’s dualism is more persuasive than Aristotelian materialism, because it accounts both for the experience of being human and research into Out of Body and Near Death Experiences.

Further, Plato’s world-view makes more sense of the human experience of morality than does Aristotle’s.  Both GE Moore in his “Principia Ethica” (1903) and later Iris Murdoch in her “Sovereignity of the Good” (1970) pointed out that we recognise goodness when it cannot be reduced to what is useful or makes people happy.  Not to be distracted by Plato’s language in relation to the forms, it is fair to say that there is an ideal of goodness which people experience as a rational intuition.  Kant described this in terms of the moral law, which appeals directly to reason as a synthetic a priori and shows all thinking people their duty to act transparently, on principle and with non-preferential humanitarian love.  Modern proponents of Natural Law like John Finnis explain what Aquinas called conscientia, the inbuilt desire to follow the direction of synderesis or what Aristotle called phronesis, in these terms.  It is difficult to explain why the way people do behave is the way they ought to behave without appealing to reason, to the sort of rational intuitions which Plato sought to explain.  The existence of a “form of the good”, howsoever this is described, explains the existence of the universal human virtues which CS Lewis and Alastair MacIntyre described and the absolute authority of agape-love which Joseph Fletcher appealed to.  Iris Murdoch developed her own version of Platonism in which she also proposed that human beings share rational intuitions of “forms” such as goodness and beauty.  This, she argued, explains why human beings seem to share the same ideas of what is good and beautiful, despite cultural and/or historical distance between them.  CS Lewis made a similar point in his “Mere Christianity” (1953), pointing out that ideas of justice exist in a similar way across time and the world.  This suggests that Plato’s philosophical approach makes more sense of human experience than scientific materialism, based on Aristotle’s philosophical approach, which tries to reduce morality and aesthetics to utilitarianism or evolutionary advantage.

Finally, the existence of innate ideas explains human language acquisition more convincingly than any other hypothesis.  As Noam Chomsky argues, human beings seem hard-wired for language, sharing a common conceptual and grammatical framework which needs only to be expressed through the conventions of a particular language.  Infants acquire language much more quickly than we might expect and non-human species (like chimps, dolphins and parrots) face an insuperable obstacle to using language rather than just naming things.  That no animal can talk is about much more than their lack of verbal dexterity, it is about their lack of the necessary neurological structures.  As Wittgenstein remarked in a different context, if a lion could talk we could not understand him.  Nativist theories of language acquisition like that of Chomsky would say that this is because the lion’s language would employ a whole other conceptual and grammatical framework as well as because the lion’s form of life is necessarily alien.  This shows that Plato’s philosophical approach, and particularly his belief in innate ideas, accounts for the evidence concerning human language acquisition better than Aristotelian materialism has.

In conclusion, despite the continued popularity of Aristotle’s philosophical approach, recent developments in both science and philosophy suggest that it is Plato’s approach which holds more interest going forward into the 21st century and beyond.

TRADE C video (simple)

TRADE C is a really simple way to structure an argument, whether in writing – such as for a GCSE AO2 answer or A Level essay – or when presenting an argument orally, such as in a debate. 

THESIS:  Begin by stating what you will argue in the simplest, clearest terms possible.  Answer the question, in a sentence, always using the wording of the question to signpost that this is your thesis and that you have answered the question.  

  • For example, if the question is “Capital punishment is never justified!” Discuss, your thesis might be “Capital punishment is sometimes justified.” 
  • For another example, if the question is “Critically evaluate the view that abortion is never justified”, your thesis could be “Abortion is never justified.” 
  • For a final example, if the question is “Critically compare Aquinas’ version of natural law with John Finnis’ version of natural law.  Which offers the most practical approach to making decisions about sex in the 21st Century?” then your thesis could be “Aquinas’ version of natural law offers a more practical approach to making decisions about sex than John Finnis’ version of natural law.”

REASONS:  Follow your thesis with 2/3 developed reasons to support your argument.  Conclusion because of this, this and that.  At GCSE a developed point is 3 sentences, Point, Evidence (ideally a quotation), Explanation – so at GCSE PEE, PEE, PEE.  At A Level a developed point follows the same PEE structure, but is more detailed, so demands a Link sentence at the end of each point to connect it back to the Thesis – so at A Level PEEL, PEEL, PEEL.  

AGREE:  Remember to include reference to a scholar and/or religious denomination who agrees with your argument.  You can either use scholarship / religious teachings in the Evidence of your Reasons paragraph, or failing that add another developed PEE(L) point here.  At GCSE you cannot get more than half the AO2 marks without referring to Religious teachings.  At A Level, you would struggle to get many marks at all – A01 or A02 – without referring to Scholarship, so a single point is a bare minimum… aim to get Agree into every Reasons paragraph. 

DISAGREE:  In the second half of your answer, outline at least one – ideally two – counterclaims, relating each to Scholarship and/or Religious teaching.    Point, Evidence (ideally quotation), Explain, Link back to your thesis, showing the implications of this counterclaim for your argument.  PEEL, PEEL

EVALUATE:  Either after each counterclaim or after you have outlined both, explain why you do not find the counterclaim convincing, using evidence (including quotations, scholars, religious teachings) and defending your thesis.  You MUST make judgments about the counterclaims in this section, signposting that you are doing this by using phrases such as:

  • This argument is poorly supported because…
  • This is not persuasive because…
  • This does not follow because…
  • This seems to ignore the fact that…  therefore this argument is weak…
  • This argument makes the assumption that… which is unreasonable because…

Evaluation is the key to getting high marks at both GCSE and A Level, so don’t cut this section short and make sure that you develop it as much as possible, using evidence to back up your judgments and making clear LINKS to the thesis after each evaluation point to show how you are advancing and defending your argument, not just describing ways to attack it!  PEEL PEEL.

CONCLUSION:  Finish your answer / essay by starting a new paragraph with “In conclusion” then restating your Thesis, using exactly the same words.  This signposts the fact that you have answered the question and proves that your argument has been coherent and well-structured (i.e. the Thesis and Conclusion match!).  If you have time, follow this by summarizing your best reason(s) and by acknowledging any limitations your argument has (i.e. what might change your mind, what your argument depends on, any areas for further consideration or research) and the implications of your conclusion (i.e. how people should think or act going forward).  PEEL

So, in summary…


  • T, RA(pee), RA(pee), DE(peel), C

A Level:

  • [Intro]T, RA(peel), RA(peel), RA(peel), DE(peel), DE(peel), C(peel)

NB: Be very careful about Introductions, either at GCSE or A level.  There is a big temptation to write down lots of irrelevant background information and forget to get down to the business of arguing your case until it is too late.  Stick to clarifying the wording of the question and/or limiting the scope of your answer.  

Critically assess Kant’s criticisms of the Ontological Argument. [40]

Immanuel Kant criticised what he first termed the Ontological Argument at the beginning of his Critique of Pure Reason (1781). Focussing on the argument as presented by Rene Descartes, which suggested that existence is a perfection and thus a necessary attribute of God, who is a supremely perfect being, in the way that having three sides is a necessary property of a triangle or having valleys is a necessary property of being a hill – Kant concluded that the argument was “so much labour and effort lost”. For Kant, existence is not a perfection and is wrongly used as a predicate. He used the example of a sum of money – the difference between a real and imaginary sum is not that the real sum is worth more, just that the real sum might be in my pocket. Existence is not a predicate and does not describe the properties of an object, it just informs me whether there is such an object in the real world. Bertrand Russell developed this point, using the example of the claim “the present King of France is bald”. Russell pointed out that although the claim seems sensible, as if it is referring to the properties of the King of France’s head and might be either true or false, in actual fact, the claim is meaningless because there is no present King of France for the claim to refer to and thus no way that the claim is either true or false. Existence is not a predicate, it is not just another property that the present King of France does or does not have, it is the ground of meaning on which all sensible claims must be made. Michael Palmer used another example to explain this; that of two candidates applying for a job. If a panel is faced with two CVs listing the “perfections” of the candidate A and candidate B, it would be ridiculous to list “exists” as one of them – existence is neither a perfection nor properly used as a predicate, rather it is what makes the analysis of the CV and the contest between the candidates meaningful. Kant’s criticisms of the Ontological Argument were highly influential and following the publication of the Critique of Pure Reason in 1781, scholarly interest in the Ontological Argument declined steeply. Nevertheless, developments in the second half of the 20th Century showed that Kant’s criticisms are far from conclusive and reawakened scholarly interest in the Ontological Argument for God’s existence.

While Kant’s criticisms were directed at Descartes’ Ontological Argument, they are often applied to the arguments of St Anselm of Canterbury, presented in his Proslogion (1078). Anselm argued that if God is “that than which nothing greater can be conceived of” then God must, a priori, exist because it is greater to exist in reality than just in the mind, so if God existed only as an idea in the mind (as he must, if Anselm’s definition was accepted) then something greater could conceivably exist… something that existed in reality as well as in the mind. If God is, therefore, the greatest conceivable being then God must exist in reality, because existence is a perfection which makes something greater. Clearly, Kant’s arguments that existence is not a perfection and that existence is wrongly used as a predicate seem to undermine Anselm’s argument fatally. As Gaunilo of Marmoutiers had observed in his “On behalf of the fool”, the idea that the perfect island has to exist just by virtue of being the perfect island is absurd; nobody is going to book a ticket to go there on the basis of an argument like that. Nevertheless, that ignores how Anselm developed his argument in the next chapter of the Proslogion, a point that he made in response to Gaunilo’s attack by restating this part of the argument in his Responsio. In Proslogion Chapter 3 Anselm reasons that it is better to exist necessarily than to exist only contingently, therefore necessary existence – not being able to not exist – must be an attribute of that than which nothing greater can be conceived of. This development of the Argument could defeat Kant’s standard criticisms, in that while existence is not a perfection or rightly used as a predicate, that does not necessarily apply to necessary existence, which is a total state of existence either possible or impossible, not a property which might or might not be added to a object that could only ever contingently exist.

Norman Malcolm argued that Anselm’s argument in Proslogion 3 can be presented in terms of modal logic. Either God’s necessary existence is impossible – as in it contains a formal contradiction – or possible. If God’s necessary existence is possible, then it is necessary.   Remember, necessary existence is not existence in the sense that we could encounter through our senses. The world of sense is a world in which things exist contingently and might or might not exist, as St Thomas Aquinas observed in his Third Way to God (Summa Theologica I.II QIII). To exist necessarily is to exist in a different way, a way that is by definition beyond anything that we could experience through our senses. For Kant, because necessary existence is beyond possible experience, then it can only be speculative to even speak of it. Kant called necessary existence a “cupola of judgement” meaning that it strays so far beyond possible knowledge to be a flight of fancy or a castle in the air. Nevertheless, this assumes Kant’s world view and the primacy of sense-experience. For rationalist philosophers like Descartes, Leibniz and later Malcolm, what is real cannot be limited to what can be experienced through the senses. The world of sense is faulty, partial, subjective and limited; empirical knowledge is contingent and ever-changing. For Descartes and Leibniz, rational knowledge should be primary because it is none of these things. A clear and distinct idea, an idea which contains no contradictions, is certain, complete, objective and constant. Just as we know that 1+1=2 without resorting to a posteriori reasoning based on experiences with apples and oranges, we know that God necessarily exists a priori because he is supremely perfect. Alvin Plantinga and William Lane Craig have developed this line of reasoning, using the device of possible worlds. A concept is possible if it could be instantiated in any possible world. A unicorn is a possible concept; although unicorns (at least in the sense of being live horses with single horns!) don’t exist in this world, it is not inconceivable that they might exist in a multiverse. The concept of a horse with a horn is not contradictory, it is possible. On the other hand, a square circle is impossible and could not exist in any possible world because the definition of a square is to have four straight sides, something which directly contradicts the definition of a circle. God’s “maximal greatness” – which must include Omnipotence, Omniscience and Omnibenevolence – is possible not impossible and, because maximal greatness precludes the possibility that God might or might not exist in any one universe, God must necessarily exist in every possible world, including this one. In essence, Plantinga and Craig show that Kant’s criticisms of the Ontological Argument fail because they rely on an impoverished epistemology.

To explain this, for Kant, all existential claims have to be synthetic, they have to refer to something in the world of sense-experience and therefore contain the possibility of being either true or false. If I say “unicorns exist” I am making the claim that there are such things as unicorns in the world – if I saw a unicorn I would know that the claim was true and if no evidence of unicorns has ever been found it is probably fair to say that the claim is false. Making the claim “God exists” does not refer to anything in the world of sense experience and it is not possible, therefore, for the claim to be either true or false… in the terms of the Logical Positivists, it is a meaningless claim. In 1951 American Philosopher WV Quine attacked the basis of Kant’s objections to the Ontological Argument in his essay “Two Dogmas of Empiricism”. Like Karl Popper and AJ Ayer, as a young man, Quine had spent time with the Vienna Circle of Logical Positivists, but by 1950 Quine came to reject their approach, not only to establishing meaning in language but also to bigger questions about epistemology – “what can we know?” and “what does it mean to say that something exists?” Logical Positivists were Positivists, that is to say that they approached philosophy on the basis that scientific, empirical observation is the only source of knowledge and that metaphysics is a waste of time. Positivism formally began with the work of French philosopher Auguste Comte, but looked back to Kant and before that to Hume and Locke. Locke rejected continental rationalism and argued that human beings have no innate ideas, being born as tabula rasa and gaining all their knowledge and understanding from experience. Hume agreed to a large extent, although he acknowledged the limitations of sense-experience as well. Kant said that Hume “awoke me from my dogmatic slumbers and gave a new direction to my philosophical enquiries” and adopted Hume’s fork, the categorisation of possible knowledge into either what is known analytically or what is known from sense-experience, dismissing any other claimed knowledge – including most metaphysical and religious claims – as speculative. Scientific method drew on the work of Locke, Hume and Kant in that it came to focus on sense-experience as the source of all new knowledge and limiting the role of reason to one of analysis and clarification. It is fair to say, therefore, that the Logical Positivists were empiricists. Quine rejected empiricism, and the Logical Positivism of his youth, arguing that in embracing Hume’s fork Kant had awoken from one set of dogmatic slumbers only to fall into another set of dogmatic slumbers. On what basis, Quine asked, did the Logical Positivists claim that sense-experience is the only source of new knowledge? The Logical Positivists failed to provide an adequate explanation of why meaningfulness should depend on either sense-experience or logic and on nothing else. This point was later developed by Alvin Plantinga in his “God and Other Minds” when he pointed out that the Verification Principle is itself unverifiable and therefore self-defeating. Quine also questioned the lack of any adequate explanation for the authority of logic, pointing out that you have to accept logic in order to defend why you should accept logic, which is circular. The same applies to the authority of the empirical senses, Quine argued. On what basis do we say that the sense-experience are the only source of new knowledge without just appealing to sense-experience? This is pure reductionism and again, the justification for Positivism is circular. The answer is that the Logical Positivists adopted Kant’s world-view without much thought, ignoring the fact that Hume (not to mention Descartes) had already outlined the serious problems with relying on the senses in that they are faulty, limited in scope and that data always needs to be interpreted through reason anyway. If Quine is correct and Kant’s epistemology is more dogmatic than critical, then his criticisms of the Ontological Argument start to collapse. On what basis did Kant claim that all existential claims have to be synthetic? For Quine, he had no adequate justification for assuming the authority or primacy of sense-experience, other than by appealing to that same sense experience. Without any proper justification for his epistemology, it seems that Kant’s criticism of the Ontological Argument is on shaky ground indeed.

Further, to say that sense-experience is the only source of new knowledge is to relegate whole fields of study, discussion and indeed human experience to junk status. The fact that the Verification Principle proposed by the Logical Positivists as the gold standard of meaning had to be liberalised through the 1930s and 1940s shows that the claim that discussions about topics such as Ethics, History and Aesthetics (let alone Religion) are meaningless is unworkable and runs against what most people believe and experience. Quine proposed an alternative holistic approach called Ontological Naturalism, which moved away from the attempt to define the meaning of individual statements in terms of their reference and towards assessing their meaning in terms of cohering with and contributing to the whole field of science as an explanatory framework. Popper also rejected Verificationism, proposing another, more generous and inclusive, approach to meaning in scientific terms in the Falsification Principle. Both were influential and contributed to a decline in Logical Positivism to the extent whereby by 1960 it was declared “dead, or as dead as any philosophical movement can be.” The decline of Logical Positivism demonstrates the inadequacy of Kant’s world-view for the modern world. What place has a system which claims that sense-experience is the only source of new knowledge in a world of Quantum science and particle-Physics, in which the very act of observing particles changes their state? Long gone is the idea that the senses offer human beings a transparent window on the external world, even the world of matter and energy. Today, the whole field of theoretical Physics would have to be declared “meaningless” by Schlick, Ayer and Carnap… and yet the insights it yields offer humanity unthought of technological advances… they work. Further, Physics suggests that what appears “real” to our senses is far from being solid and as it appears. On the Planck scale no matter exists… if I hit the table the contact I experience is really the interaction of charges in the fields which make up the vast majority of each atom in the wood and in my hand. The universe, which appeared like a vast machine to Kant and which still appears eternal to the amateur start-gazer has been revealed to be infinite while still having edges, a shape and a colour and while expanding at an increasing rate… into nothing. All of this suggests that reason – mathematics – can yield new knowledge and confidently move past anything we can hope to observe through our senses, to a much greater degree than either the Logical Positivists, or Kant, allowed.

On the other hand, even theoretical Physicists admit the need to test their theories through experiments. Very recently, different theories on black holes were tested when radio-telescopes were linked together to take a photograph of a black hole. The photograph – an observation – was necessary to check analytical calculations and prevent them from being purely speculative. This supports Kant’s claim that all existential claims must be synthetic. Physicists theorise about black holes, but it is not possible to say that or how they exist unless and until we take a photograph or make some other observation to verify (or falsify) the theories. Nevertheless, there are aspects of Physics – as there are aspects of Theology – which resist any possible observation. By definition, it is not possible to observe God’s necessary existence, because by definition it must be outside of the matrix of time and space in which our senses operate. Similarly, it is not possible to observe what caused the Big Bang which created the space-time continuum, or to experience conditions in a multiverse. The extent to which cosmological theories like cosmic inflation and string theory are pseudo-scientific (to use Popper’s phrase) because they are not falsifiable or subject to normal scientific method has been a matter of controversy on the letters’ page of Scientific American since 2017. Nevertheless, this should not stop Physicists (or Theologians) from using reason, the other source of knowledge available to them, to push forward the boundaries of knowledge. While Kant was right to be cautious and to warn against metaphysical speculation – because after all, the greatest obstacle to finding something is being convinced that you already have it – his world-view with its focus on the senses as the arbiter of possible knowledge is too restrictive for the 21st Century in the way that the world-view of the Logical Positivists became too restrictive for the 20th Century. It also sits ill with both developing insights about the way in which our senses work and rely on our brains and pre-existing ideas and with insights about the different reality beyond how things appear to our senses, on the Planck scale. While Popper’s Falsification Principle is more flexible than the Verification Principle, it still limits what can be said scientifically to that which can be falsified in relation to observations, it still assumes a Kantian world-view, and herein lies the problem for particle Physics and Cosmology with Scientific Method as it is conceived today. It seems that Kantian epistemology and the assumed world-view within which science has operated since the 1790s is on the verge of being rejected; to use Thomas Kuhn’s phrase, the Positivist scientific (and philosophical) paradigm is shifting and giving way to a paradigm which is more open to reason providing new knowledge which cannot be checked by observation. Given this, it seems that Kant’s criticisms of the Ontological Argument will lose a great deal of their power. As William Lane Craig has pointed out, the Ontological Argument (as he presents it) is valid. If it is accepted that an argument can also be sound – its propositions can be said to be true – even when they cannot be verified or falsified empirically, then the Ontological Argument is much more persuasive.

Nevertheless, even if Kant was too cautious about using reason as a source of new knowledge, it could be fair to say that the Ontological Argument pushes things too far. St Thomas Aquinas made just this point in his Summa Theologica I.II question 1 (1264) when he wrote “because we do not know the essence of God, the truth of God’s existence is not self-evident to us.” Aquinas dismissed the Ontological Argument because to suggest that any human being can have a “clear and distinct idea” of God to use Descartes phrase from the Meditations, sufficient to analyse that idea and find necessary existence – a unique property of God – within it, is arrogant. God is, to use Augustine’s words “other, completely other”, outside time and space, so even if we have innate ideas – as Descartes and Plato argued – it stretches credulity to rely on those ideas being so complete in relation to God so as to make the Ontological Argument plausible. Clearly, what it means for God to be perfect or great is not what it means for human beings to have a perfection or be called great. Aquinas even rejected the idea that it could just be a matter of scale, with God at the top of the scale and people (and other created things) at the other. If God is timeless then God’s perfection and greatness must also be timeless and cannot include any potential for God to be other than he is, to change or to choose. Aquinas’ saw claims about God’s nature as necessarily analogical. Yes, our greatness depends on God’s greatness, but in the way that the healthiness of a yoghurt depends on the healthiness of somebody who eats it. Healthy people are slim, muscly and bounce around… healthy yoghurts are none of these things! For Aquinas, God’s nature can be described (and known) positively, but only in a very limited sense, not completely enough to support an ontological demonstration of God’s necessary existence from an a priori definition of His nature. Nevertheless, St Anselm and Descartes on one hand and Karl Barth and Iris Murdoch on the other would all reject this argument, with reasons that also serve as criticisms of Kant’s approach to the Ontological Argument.

For Anselm it is true to say that God’s attributes are not the same as human attributes, because God is timelessly perfect, nevertheless it is possible to understand enough about God’s greatness to deduce that necessary existence is a necessary property of it. This is because, according to the a posteriori argument in Anselm’s Monologion, God is the best explanation for our ability to judge things in this world as more or less perfect. God creates us with an innate conception of perfection, the top of a scale which we use to measure things in this world every day. Indeed, Aquinas – although he still denied that this would give people a clear enough concept of God to analyse and find necessary existence within – included a similar argument as his fourth way to God in Summa Theologica I.II question 3, arguing that claims about God’s nature can be understood as analogies of proportion as well as as analogies of attribution (as above). This suggests that Aquinas’ rejection of Anselm’s approach was more about the degree to which we can conceive of the essence of God and a matter of interpretation, rather than about Anselm’s whole methodology in the Monologion, which he later used to support his reasoning in the Proslogion. Descartes “trademark” argument in the Meditations supports Anselm’s belief that God creates us with an innate idea of God’s existence and there have been other, similar arguments in the work of scholars from St Augustine to CS Lewis, arguing from the experience of believers, their desire for and innate awareness of God, a posteriori to the conclusion of His existence. It seems that many believers could accept the idea that we have an understanding of God’s supreme greatness even if we cannot completely conceive of what that might entail. It seems, therefore, that Aquinas’ dismissal of a priori attempts to argue that God’s existence is self-evident is rather hasty. Just as Aquinas’ rejection of the idea that God’s existence is self-evident and exclusive focus on arguments from observation as the only approach to defending God’s existence rationally does not fit with believers’ experience of God as an innate idea, Kant’s rejection of both a priori and a posteriori arguments for God in the Critique of Pure reason does not fit with the imperative to believe in God which he himself expressed in strong terms, most completely in “Religion within the bounds of Reason alone” (1794). While Kant dismisses all the rational arguments for God’s existence, including the Ontological Argument, he argues that God is a necessary postulate, an assumption that it is our rational duty to make, to explain the existence of the moral law which we know as a synthetic a priori. Kant reasons, therefore, that we know the moral law a priori, before experience, although it is supported in all respects by experience as well. The moral law is, furthermore, necessarily explained by God. On what basis can Kant argue that Descartes is wrong to claim that we know God’s existence a priori, something which is supported in all respects by experience as well, but proceed to make a similar claim about the moral law. It is worth asking, is Descartes concept of God actually different from Kant’s concept of God? All that Descartes attempts to demonstrate through his Ontological Argument is that Supreme Perfection necessarily exists… he makes no claim about the Ontological Argument proving anything about the nature of that Supreme Perfection, stopping short of listing attributes like being male, being the father of Jesus etc. Is it fair to claim that the moral law can be known a priori – as Kant does – and reject the idea that the necessary existence of Supreme Perfection cannot be known a priori, when both seem equally borne out by experience.

Further, Karl Barth (and later Iris Murdoch) pointed out that the Ontological Argument, although not conclusive as a proof of God’s existence for the non-believer, it is deeply persuasive for the person with faith. In Barth’s “Faith Seeking Understanding” (1930), far from pre-empting Norman Malcolm’s claim that the Proslogion was an exercise in modal logic (a claim that has been accepted by Hartshorne, Plantinga and Craig), Barth argued that Anselm’s work had been wrongly characterised as a philosophical treatise and argued that it was really a prayer, a deeply spiritual meditation on contingency and necessity and the nature of reality. If Barth is correct then Kant’s criticisms of the argument, at least as they are applied to Anselm rather than their intended target, Descartes, are misplaced. To say that Anselm’s work is “so much labour and effort lost” misses the point that he may not have intended to formulate a deductive proof such as to convince a non-believer at all. Further, while the philosophical intent behind Descartes’ arguments in the Meditations is difficult to deny, it is worth mentioning that this work too was written from the perspective of pre-existing faith. Descartes too had “faith seeking understanding” and was not engaged in a work of Christian apologetics. Kant’s criticisms approach Descartes’ ontological argument for God in isolation and attempt to dismantle it from the perspective of a radically different world-view and epistemological framework. Given the doubt that has been cast on the possibility of attaining objective Truth and a grip on ultimate reality – a doubt that was adopted by Kant from Hume but which was often subsequently ignored – the idea that Kant’s world-view and epistemological framework, which as has been explained rests on as many assumptions as does Descartes, should have the authority to dismiss Descartes’ Ontological Argument is unconvincing. Today, most philosophers have to look to coherence rather than to correspondence to find meaning, and thus have to be open to the possibility that an Ontological argument might be both valid and sound within one form of life and simultaneously valid but not sound in another form of life.

In conclusion, Kant’s criticisms of the Ontological Argument are effective only if his epistemology and world-view are accepted.