Tag Archives: Critical Metaphysics

Hume vs. the Rationalists

For referencing Hume’s work, I have adopted what appears to be the standard form of paragraph notation, with the letter ‘T’ (for the Treatise) or ‘E’ (for the Enquiry) along with the paragraph number where available.


Hume’s ‘empirical project’ was an attempt to dispense with uselessly abstract rationalist metaphysics which posited ideas beyond what could reasonably be known, and encourage a new ‘science of man’ to replace it.  The key part of this project was to support sense-experience as the source of knowledge about the world, in direct opposition to claims of the rationalists who appeal to innate and a priori knowledge of the world.  The implications of Hume’s project had far reaching effects, particularly highlighted in relation to Hume’s attack on the notion of causation.  First, there will be a brief discussion of Hume’s ‘empirical project’, and its position in the Rationalist vs. Empiricist divide.  This will be followed by Hume’s theory of ideas. Finally, we will consider Hume’s arguments on causation, considering the radical change from the rationalist position.

Hume’s Empirical Project, and Rationalism vs. Empiricism

Hume’s ‘empirical project’ was a reaction against rationalist metaphysics.  The crux of the debate was over epistemology; the nature of our sources of knowledge.  It is a question about how we know certain propositions. A Rationalist view generally considers it possible that some knowledge is certain and immutable; because some, or all of our knowledge can be discovered ‘a priori’, without experience, whether this is ‘innate knowledge’, ‘innate concepts’ or through ‘intuition [and] deduction’ deduction’ (Markie, 2012).  Consider Descartes’ innate ideas of himself as a thinking thing, as well of his idea of God (Descartes, 2008, pp. 18, 37).

However, Hume considered the Rationalist argument to be generally inconsistent, and sometimes completely incompatible (Dicker, 1998), even though this knowledge was supposed to be known beyond doubt, a priori.  Instead of this ‘false’ metaphysics (E, S1.12 Hume, 2007), Hume proposed a new ‘science of human nature’ (E, S1.1) which would provide satisfaction in knowing what it is possible to know (E, S1.13) but also would curb the excesses of the ‘abstruse philosophy’ which has ‘sheltered… superstition’ (E, S1.17).  This would be an empiricist view, which did not rely upon these notions, claiming instead that humans are essentially born as a ‘tabula rasa’ (Locke, 1690), a blank slate, upon which all knowledge is written by way of experience, ‘a posteriori’. As Scruton (2002) notes ‘there can be no concept except where there is experience’ (p. 123).  However, Hume goes even further, to argue that our beliefs in such things as causation, substance and self are purely inferences that we draw, rather than certain knowledge.  This has profound effects on the possibility of metaphysics as a discipline; Hume’s new science, should it succeed, would largely discard rationalist metaphysics. To begin his project, he considers the nature of experience, and the origin of our ideas.

Hume’s theory of ideas

We experience through perception: our perceptions of the mind are divided into two ‘species’ which are differentiated by their ‘force and vivacity’ (E, S2.3). ‘Impressions’, the more forceful of our perceptions contain ‘all our sensations, passions and emotions’ (T, 1.1), whether they be ‘outward’ from sensation, or ‘inward’ from reflection. while ‘Ideas’ are the ‘less lively perceptions’ belonging to the memory or imagination that we are conscious of when we reflect upon impressions (E, S2.3).  Both ‘species’ can be further subdivided as simple, that ‘admit[s] of no distinction nor separation’ (T, or complex, formed from two or more simple ones, and can be ‘distinguished into parts’ (T,; see also Merrill, p. 32).  Following from this, Hume sets as his ‘one general proposition, that all our simple ideas in their first appearance are derived from simple impressions, which are correspondent to them, and which they exactly represent’ (T1.1.1.7 in Hume, 2009).  This is often called the ‘copy principle’ (Fieser, 2011; Morris, 2009), in that simple ideas are ‘copied’ from simple impressions.

Consider this piece of paper; the visual experience of deciphering shapes on the page, the tactile sensations from the feel of the paper in your hand.  Once you place it down, and are no longer directly experiencing the direct sense impression of the paper, you have the reflective capacity to form ideas in your mind of the paper, where you can bring back an image of the paper and recall these sensations.  In this case, you could even break down the idea you have of the paper into the particular ideas about its texture, colour and the ‘inward’ sensations of how you felt reading it.  You do not ‘experience’ ideas, they are memories of experience, and can be built upon in the imagination.  Perhaps you combine your idea of this paper, and your ideas of error, and create an idea in your imagination of this paper covered in red crosses! From multiple simple ideas, a complex idea has formed in the imagination, even though this object does not exist (yet).  However, the reverse is also true; by considering our ‘complex’ ideas, whether from memory or imagination, we can break them down into their component parts to find the ‘impressions’ from which they are derived.  It is through this method that Hume claims we can identify whether our ideas have meaning.

When we want to determine whether a term or concept has meaning, ‘we need but enquire, from what impression is that supposed idea derived?’ (E, 2.9) If we are unable to find its simple impression, then ‘this will serve to confirm our suspicion’ (E, 2.9) that they are meaningless.  Our ideas are not simply the materials of thought, but also the arbiters of meaning (Noonan, p. 93).

So, to consider the limits of human reason, Hume divides it into two categories.  The first, ‘Relations of Ideas’, concerned with definitions and mathematical-logical relations, allows some ‘intuitively certain’ knowledge.  However, this knowledge is limited in scope to demonstrable propositions which do not assert or imply the existence of ‘non-abstract identities’ (Dicker, 1998, pp. 36, 37, 39) because they simply show the relations between entities.  Consider mathematics; the proposition that 1 + 2 = 3, and we find that all this statement tells us is the relations between these three numbers (E, 4.1.1).  The second, ‘Matters of Fact’ are truths about the world which either assert or imply existence (Dicker, 1998, pp. 36, 37, 39); however these can only be obtained through experience.  That this keyboard will work this afternoon is a matter of fact; from considering that it is working as I type this, I induct from this the ‘fact’ that it will work later today; however this proposition can be falsified, because unlike the demonstrably true ‘relations of ideas’, there is no contradiction in this proposition.  This separation of ‘knowable propositions’ (Dicker, p. 36) has been termed ‘Hume’s fork’ (see Dicker; Merrill; Fieser).

These matters of fact are connected through various relations; our knowledge of the world relies upon assuming a regular ‘association of ideas’ (T, 3.8; E, 3).  This association of ideas centres around three ‘principles of connexion’ (E, 3.2) which allow for ‘transitions in thought … [and] explaining belief’ (Noonan, 1999, p. 73); ‘Resemblance’, where an impression prompts an idea of something which it resembles; ‘Contiguity in time or place’, where an impression prompts an idea of a further idea which was encountered at a similar time, or in a similar place; and ‘Cause or Effect’ (E, 3.2;  see also Noonan, 1999, p. 71).  The causal relation is the most important of these, because all of our reasoning concerning ‘matters of fact’ are founded on it, and it is the only one of the three relations which ‘can be traced beyond our senses and informs us of existences and objects, which we do not see or feel’ (T, 3.2; E, 4.4).  This brings us to our investigation of how Hume’s project radically shifted the understanding of causal relationships, against the rationalists.


The Rationalists had different conceptions of the nature of causality; Descartes’ takes it to be innate (Markie, 2012), Leibniz would present it as a form of ‘pre-established harmony’ between two ‘created’ substances (78, 79 in Leibniz, 2010; Bobro, 2009).  Both of these thinkers also allow for the interaction of their deity, which was also generally conceived to be the ‘first cause’.  What is common between them is that they all considered causal relations to ‘have an objective necessity’ that could not entertain doubt, as this notion did not come from sense-experience (Wilson, 2004, p. 267).  Hume, using his new theory of ideas, challenges: the possibility for innate ideas, through the empirical claims that ideas stem from experience, which determines its possible content; and also challenges the justification of causal relationships using ‘objective necessity’.  It is to this challenge on causal relationships that we now turn.

As discussed earlier, Hume claimed that all ‘matters of fact’ were grounded in experience, and depended on causal reasoning (E 2.2.14 in Hume, 2007, p. 23).  We also noted his claim that any attempt to go beyond the current contents of our sense experience requires considering the cause-effect relationship.  So, he endeavours to find the empirical evidence for our ‘knowledge’ of cause and effect.  Directly against the rationalists, he claims that we ‘know’ that a priori reasoning will not give us this knowledge (E, 4.6) since the effect is ‘totally different from the cause’ (E, 4.9).  With many different possible outcomes for any particular event, and no foundation for the preference of any particular outcome in ‘reason’, experience is required.  Any a priori attempt to ‘reason’ the effect from the cause without experience will mean inventing or imagining the event, and with nothing in the cause will be ‘entirely arbitrary’ (E, 4.11).

With the rationalists being denied innate ideas, and been dealt a strong blow to their understanding, Hume’s project continued.  Since the foundation of all reasoning concerning causal relations was experience, He wanted to know how it was that we come to our conclusions.  His answer was our experience of ‘constant conjunction’ of our ideas over a period of time (T,  However, while we may observe two events that occur in conjunction, there is no way for us to know the nature of their connection. Consider this essay once again; if its author had developed a complex idea of ‘red crosses on marked essays’, and was aware of a constant conjunction of events, whereby at each instance of an ‘essay submission’ event previously, the author received red crosses, the author may infer based on the submission alone, that this essay will also be returned with red crosses.  Hume makes this explicit as two propositions:

‘I have found that such an object has always been attended with such an effect, and I foresee, that other objects, which are, in appearance, similar, will be attended with similar effects’ (E, 4.16)

We often implicitly assume the ‘Principle of the Uniformity of Nature’ (Lorkowski, 2010), in that we expect tomorrow to be like it was today.  However, is not contradictory to conceive of a change because there is nothing implicit in the first object that makes it necessary for a particular effect. It is for this reason that Hume considers inductive reasoning, whereby we generalise a conclusion based on a particular, to be weak; it leads to what is often known as the ‘problem of induction’ (Lorkowski, 2010). Hume claims we have no reason to appeal to past experience, because

‘reason can never show us the connexion of one object with another, tho’ aided by experience, and the observation of their conjunction in all past instances … it is not determined by reason, but by certain principles, which associate together the ideas of these objects and unite them in the imagination’ (T,

Rather than good reasoning, Our notion of causation is actually a ‘custom or habit’ (E 5.6; E 7.30).  Our belief of causation is formed by ideas  becoming ‘enlivened’ (E, 5.15) by a new impression that bears a relation to it.  While this belief stems from our very nature (E, 5.22), it is unfounded and meaningless according to his verification principle.  In spite of all this, Hume allows that we can still use induction, like causation, to function on a daily basis as long as we proportion the effect to the cause without ascribing qualities in excess of what can be known (E, 11.12; 12.25; 12.26).


Hume’s empirical project presents a strong challenge to rationalist metaphysics, showing us that we are, perhaps, not as rational as we once supposed, and the world is not as ordered as we assumed.  While the rationalists offered certain knowledge, at least for their own ‘brands’ of rationalism, Hume’s empiricism requires us to be uncertain, and always being aware of our limits.  For Hume, the Rationalist metaphysics was unacceptably abstract, and, in their denial of sense-experience, were contradictory.  With causation being so heavily implicit in our daily life, realising that we are much more creatures of habit rather than ‘rational animals’ goes some distance to show that appeals by the Rationalists for ‘innate ideas’ and a priori knowledge are unfounded; our knowledge is neither sure, nor as well grounded as the rationalists have posited.


Bobro, M. (2009) ‘Leibniz on Causation’ in E. N. Zalta, (ed.) The Stanford Encyclopedia of Philosophy,Spring 2009 ed.,  [online], available: http://plato.stanford.edu/archives/spr2009/entries/leibniz-causation.

Descartes, R. (2008) Meditations on First Philosophy: with Selections from the Objections and Replies, Oxford World’s Classics, Oxford:Oxford University Press.

Dicker, G. (1998) Hume’s Epistemology and Metaphysics: An Introduction, New York:Routledge.

Fieser, J. (2011) ‘David Hume (1711-1776)’ in The Internet Encyclopedia of Philosophy,[online], available: http://www.iep.utm.edu/hume/#H2.

Hume, D. (2007) An Enquiry Concerning Human Understanding, Oxford World’s Classics, Oxford:Oxford University Press.

Hume, D. (2009) A Treatise of Human Nature, The University of Adelaide Library [online], available: http://ebooks.adelaide.edu.au/h/hume/david/.

Leibniz, G. W. (2010) The Monadology, Adelaide:The University of Adelaide Library.

Locke, J. (1690) ‘Book I: Innate Notions’ in An Essay Concerning Human Understanding,[online], available: http://www.earlymoderntexts.com/f_locke.html.

Lorkowski, C. M. (2010) ‘David Hume: Causation’ in The Internet Encyclopedia of Philosophy,[online], available: http://www.iep.utm.edu/hume-cau/#H2.

Markie, P. (2012) ‘Rationalism vs. Empiricism’ in E. N. Zalta, (ed.) The Stanford Encyclopedia of Philosophy,Summer 2012 ed.,  [online], available: http://plato.stanford.edu/cgi-bin/encyclopedia/archinfo.cgi?entry=rationalism-empiricism.

Merrill, K. (2008) Historical Dictionary of Hume’s Philosophy, Historical Dictionaries of Religions, Philosophies, and Movements, No. 86, Maryland:The Scarecrow Press, Inc.

Morris, W. (2009) ‘Meaning(fullness) Without Metaphysics: Another Look at Hume’s “Meaning Empiricism”’, Philosophia, 37 (3), 441-454.

Noonan, H. W. (1999) Routledge philosophy guidebook to Hume on Knowledge, London:Routledge.

Scruton, R. (2002) A Short History of Modern Philosophy: From Descartes to Wittgenstein, Routledge Classics, 2nd ed.,  New York:Routledge.

Wilson, F. (2004) ‘Empiricism: Principles and Problems’ in W. Sweet, (ed.) Approaches to Metaphysics,Dordrecht: Kluwer Academic Publishers, 265 – 300.



Descartes on God

After carrying out his systematic doubt, and introducing the possibility of complete and constant deception, Descartes’ finds himself lost in a lonely solipsism, with only the indubitable knowledge that he exists, and that he is a thinking thing. He seeks a way to extricate himself, and to provide a new epistemic foundation to replace the scholastic tradition he inherited. The knowledge he has gained thus far does not seem to be able to help him; He decides that he must ‘examine whether there is a God’ as soon as possible, for without a God, he could not be sure of anything (Descartes, 1986, p. 25). Not satisfied with previous arguments for the existence of a supreme being, Descartes aimed at not only showing the ‘necessity’ of a divine being, but wanted to link this being with that of his Judeo-Christian religious traditions. He offers two primary arguments for Gods existence in his ‘Meditations on First Philosophy’; one in the Third Meditation, and one in the Fifth. Importantly, these ‘proofs’ are not extraneous to his undertaking, but are central to it; If these proofs fail, so too does a considerable portion of his project. Therefore, it is important to carefully examine these arguments and highlight any problems with the proof, and how these might be answered. The causal argument of the Third Meditation and the ontological argument of the Fifth Meditation will be standardised and analysed to determine if these proofs succeed. However, In order for readers to follow his reasoning, and to aid in a charitable examination, a necessarily brief and tailored introduction to Descartes’ theory of ideas will be presented.

Firstly, since Descartes’ is currently only certain that he is a ‘thinking thing’; the next most logical step for him is to look at his thoughts (Williams, 1978, p. 116). He introduces a category of his thought as ‘ideas’, which are ‘images of things’ (Descartes, 1986, p. 25). Descartes does not mean to imply that ideas must be a pictorial image, so a less ambiguous meaning might be ‘representations of objects’ (Beyssade, 1992, p. 179). He further informs that these ideas, ‘considered solely in themselves’ without being referred to anything, cannot be false (Descartes, 1986, p. 25). However, he needs to discover where these ideas came from.

Descartes’ provides three mutually exclusive options; ideas can ‘innate’, wholly from within; ‘adventitious’, provided from sensory experiences; or ‘invented’ by the imagination (Descartes, 1986). At this stage, Descartes’ does not know which ideas fall into these categories, because he has been deceived before, so to use this understanding, he must investigate whether any ideas actually resemble their objects. When considering his ideas as ‘modes of thought’, they are equal; they cannot be distinguished by their source, or their degree of reality. However, when looking at what his ideas represented, order began to present itself; His ideas ‘formal reality’ may not differ from one another, however it was clear to him that their content modified the ideas ‘objective reality’ (Descartes, 1986). Based on this, he claims that substances ‘amount to […] more’ and so must contain more ‘objective reality’ than that of modes and accidents (Descartes, 1986, p. 28).

This notion of things having different degrees of reality is important for Descartes’ argument. He wants to invoke the ‘scholastic distinction’ of formal, eminent and objective reality. For Descartes, substances have the quality of independent existence (Williams, 1978, p. 121), and so have ‘formal’ reality intrinsic to their nature. Likewise, an idea of a substance has ‘formal’ reality as a ‘mode of thought’, however also has ‘objective’ reality based on the substance it represents.

Using the foundations he has set, he looks at his various ideas, to determine if there are any ideas within him that could not have been produced by him. He considers various substances, and finds that he could have produced all of these, except for one: his idea of God. This idea, of a God who is ‘eternal, infinite, <immutable,> omniscient, omnipotent and the creator of all things that exist apart from him’ (Descartes, 1986) has significantly more objective reality than ideas of other substances.

With an understanding of these general principles, the examination of Descartes’ arguments for the existence of God begins in earnest. In the pages to follow, the two arguments will be outlined, along with an examination of the problems and possible solutions which arise. Finally, the arguments will be evaluated on their strength.


Axiom 1: A cause provides the effect with its reality – ‘[T]here must be at least as much <reality> in the efficient and total cause as in the effect of that cause’ (Descartes, 1986).

Axiom 2: ‘Something cannot arise from nothing’, ergo, everything must have a cause.

Axiom 3: My ideas must have a cause [from A2],

Axiom 4: ‘for a given idea to contain such and such objective reality, it must surely derive it from some cause which contains at least as much formal reality as there is objective reality in the idea [from A1 & A2]

Axiom 5: Infinite regresses are not possible, both formally and objectively; ‘eventually one must reach a primary idea which will be an archetype which contains formally <and in fact> all the reality <or perfection> which is present only objectively <or representatively> in the idea’ (Descartes, 1986, p. 29).

Axiom 6: The ‘more perfect […] cannot arise from what is less perfect’ (Descartes, 1986, p. 29).

  1. IF “the objective reality of any of my ideas turns out to be so great that I am sure the same reality does not reside in me, either formally or eminently, and hence that I myself cannot be its cause” THEN “I am not alone in the world, but that some other thing which is the cause of this idea also exists.” (Descartes, 1986, p. 29)
  2. I could not possibly have been the cause of my idea of God [from 2.1, 2.2 & 2.3]
    1. I have an idea which contains an infinite amount of objective reality
      1. I have an idea of God who is ‘eternal, infinite, <immutable,> omniscient, omnipotent and the creator of all things that exist apart from him’ (Descartes, 1986, p. 29).
      2. In order to have this idea, I must have an innate idea of perfection
        1. ‘I clearly understand that there is more reality in an infinite substance than in a finite one, and hence that my perception of the infinite […] is in some way prior to my perception of the finite’ (Descartes, 1986, p. 31)
      3. Ideas in me may fall short of reality, but cannot contain more perfection
    2. I am imperfect
      1. I myself am a finite being.
        1. Finite beings have finite formal reality
  3. [from P1 & P2] ‘I am not alone in the world, something other than me must exist’ to have caused my idea of God

– – –

  1. [from A1 – A6] Only a being with infinite formal reality could be the cause of an idea with infinite objective reality.
  2. Therefore, God exists [from 3 & 4]


The proof presupposes a similarity in the cause and its effect, leading Descartes to claim the idea of God was innate within him ‘like the mark of a craftsman’ (Descartes, 1986, p. 35). However, the rationalist conception of ‘innate ideas’ has been challenged by various thinkers, including Locke and Hume (Hume, 1978; Locke, 1690). Ideas of God and religious notions are heavily dependent on cultural factors, demonstrated by the quantity of different religions around the world, and across the ages. Similarly, there are individuals and cultures that have not been brought up to believe in God, who do not naturally come to the conclusion that there is a being like Descartes describes without having ‘instruction’ in a religion. If the idea of God were truly innate, based on Descartes’ own argument, it would be expected that all people would have highly similar, if not identical, conceptions of God; this was a point highlighted in Descartes day by Gassendi. The idea of God could perhaps have simply been transmitted through social contact.

Descartes’ has a response to this. In the Objections and Replies, Descartes’ responds to several queries regarding the denial of an ‘idea’ of God. Descartes’ most comprehensive response is in the Second Replies, informing that those who deny they have an idea of God are not truly denying the absence of this idea but instead simply rejecting the name given, and claiming they don’t have an ‘image’ of God (Descartes, 1642, p. 24). He appears to think that the denial of the idea is only related to the inability to visualise God, rather than denying the ideas contents. Related to this is his response to Gassendi, where Descartes’ implies that it should not be surprising that people draw varying conclusions about their idea of God, because they may be attending to different points, or making false judgements (Descartes, 1642, p. 120). These responses do not seem to be satisfying, because if this idea were truly innate and provided by God, it seems reasonable to think there would be a greater perfection in the ‘mark’ and so leave less capacity for denial. It also leaves the question open as to how certain cultures are completely ignorant, and must be instructed in the knowledge of God.

Another possible flaw in this argument is in Descartes’ axiomatic assumption of causation. Hume argued that the notion of causation was not ‘intuitively nor demonstratively certain’, but instead relied upon ‘observation and experience’ (Hume, 1978, p. 82). Hume considers that even a posteriori causation cannot be proven with certainty, particularly in the case of first causes; there is no way to gain experience of these, and so assumptions are made based on current experience, and extrapolated to other experiences inductively (Hume, 1978). It therefore seems reasonable to ask, at the point of the third meditation, why this premise should be granted. Since we have not yet accepted the proposition ‘God exists’ in order to defeat the possibility of deception by the Evil Demon presented earlier in the Meditations, nor have we been given proof of the external world in which we could (presumably) establish this a posteriori, this axiom should be challenged.

After giving this highly complex ‘proof’, Descartes considers the reader to be ready for a simpler proof. This is the Ontological proof of the Fifth Meditation, which aims to prove Gods existence by an appeal to the ‘essence’, or ‘nature’ of God. This ‘essence’ is identified through the definition of ‘God’ as he appears to Descartes consistently across the Meditations.


Axiom 1: All things have an essence; that which defines them.

Axiom 2: ‘Even though there may not be anything outside of me, my ideas of things cannot be called nothing’ (Descartes, 1986).

  1. It is in Gods’ nature to have every perfection
    1. I have a clear and distinct idea of God ‘within me, as surely as any number’ (Descartes, 1986)
      1. Even if nothing else is true, God has the same level of certainty as any attribute of mathematics
    1. Existence is one of the perfections God has (i.e. It is more perfect to exist).
      1. ‘Existence can no more be separated from the essence of God than the fact that its three angles equal two right angles can be separated from the essence of a triangle’ (Descartes, 1986, p. 46)
      2. I cannot think of God except as existing
    2. God exists


One particular theme in the objections to this argument was the criticism that Descartes assumes that existence is a property. These objections were even made in Descartes time, with objectors claiming this argument could fall prey to proving the existence of anything (Descartes, 1642, pp. 14,31,32,52,129,132,156,157). Descartes appears to be making a considerable leap from a definition of a concept, to existence in the actual world. With this format argument, we could argue for the existence of just about anything. Mackie (1982, p. 43) illustrates this with the example of a ‘Remartian’; not just an idea of an alien from Mars, but a ‘Real’ Martian. This ‘Remartian’ would have all the qualities of a standard Martian, but with ‘existence’ built into the concept; it would become part of the essence of the ‘Remartian’. It seems that Descartes reasoning would have us accept the existence of these beings. With the assistance of Immanuel Kant, the issue was able to be articulated. Kant tells us existence is ‘obviously not a real predicate’ because ascribing existence to an object does not add or take away from it (Kant, 1999, p. 200 A599/B627). Existence is the requirement before an object can have any properties outside of their concept (Descartes, 1642, p. 132).

However, Descartes can respond to this charge; in the First and Second Replies, he appears to acknowledge this difficulty with his proof. While the existence of ‘Remartians’, or other mythological creatures may be posited, none of these have ‘necessary existence’, but only ‘possible existence’. This is not the kind of existence which must be attributed to God. In a clarification to the argument in the First Replies, Descartes claims:

  1. What he clearly and distinctly understands of the true essence of something can be asserted
  2. When we know what God is, we ‘clearly and distinctly’ realise existence belongs to this nature
  3. Therefore, God exists    (Descartes, 1642, p. 13)

The conjoining of all perfections in God makes existence a necessary feature in, and only in, the case of God (Descartes, 1642, pp. 16,132). The ‘true and immutable nature’ of God is such that he cannot be imagined without existence, unlike the contingent natures of other beings. Denying the existence of God would be a contradiction, because this being would lack total perfection.

This however, is unconvincing. There appears to be a degree of support from the arguments in Meditation Three being assumed. If we have accepted the existence of God from those arguments, then it could be granted that there is a specific implied premise here, in that without God nothing could exist; while this arguably may affect Kant’s argument, this then becomes an article of faith, since without the support from the earlier arguments, then it is unlikely that someone would grant this without further argumentation.


Descartes offers two primary ‘proofs’ for the existence of God. Both of these arguments are emotionally powerful for theists, and serve to provide justification for their belief. However, they face significant challenges to their conclusions. While there is some measure of mitigation with these difficulties, it is clear overall that these arguments do not succeed in ‘proving’ the existence of any deity.


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