God and the External World1 Martin Smith University of Glasgow There are a number of apparent parallels between belief in God and belief in the existence of an external world beyond our experiences. Both beliefs would seem to condition one's overall view of reality and one's place within it – and yet it is difficult to see how either can be defended. Neither belief is likely to receive a purely a priori defence and any empirical evidence that one cites either in favour of the existence of God or the existence of the external world would seem to blatantly beg the question against a doubter. I will examine just how far this parallel can be pushed by examining some strategies for resisting external world scepticism. I. TWO SCEPTICAL ARGUMENTS It was once commonly thought, in the philosophy of religion, that belief in the existence of God could be given a water-tight a priori defence. Few, now, think that this ambition can be realised. And, if ordinary theists are asked to defend their belief in God, they may well produce something recognisably empirical in nature. They may say things like 'I have felt the presence of God', 'God has spoken to me' or some such. They might also, of course, cite religious authority or some kind of argument from design – but I shall focus here upon the former 'divine revelation' type responses. In a way, these serve as paradigm instances of an empirical defence of a belief. The theist after all is drawing attention to (unusual, moving) experiences that he has had – experiences that he interprets as providing direct evidence for his belief in God. Interestingly, this consideration runs counter to the idea that religious belief is largely a matter of faith – at least if faith be construed as a willingness to believe without evidence2. Many ordinary religious believers would take themselves to have evidence for their convictions. 1 This paper was presented in March 2009 as part of a public lecture series at the Centre for Philosophy and Religion at the University of Glasgow. Thanks to all of those who participated on this occasion. 2 Of course, 'faith' can also be used in an epistemically neutral sense to indicate a particularly strong or heartfelt conviction. In this sense religious beliefs are very often matters of faith. 2 An atheist or religious sceptic, however, would likely remain unpersuaded by an appeal to religious experience – and quite rightly so. The atheist can grant that the theist has had the unusual and moving experiences that he is drawing attention to – but will simply deny that they provide any evidence whatsoever for the existence of God. The atheist will regard these experiences as perfectly explicable without the need for extravagant supernatural agency – they will be the product of wish fulfilment or insecurity or delusion or similarly mundane, Earthly factors. The considerations that the theist cites seem to beg the question against the atheist – one would not regard these experiences as the result of God's agency unless one already believed in the existence of God. We are tempted to reason as follows: If a belief in the existence of God is based solely upon question-begging grounds, then it is not based upon genuine evidence, in which case it is unjustified. I strongly suspect that empirical defences of religious belief based upon religious authority or design arguments will be questionbegging in essentially the same way, but I won't pursue this here. Some philosophers have attempted to press a certain comparison between scepticism about the existence of God and more radical kinds of scepticism – such as scepticism about the existence of the external world. One of the first to pursue this line was John Henry Newman in his Sermons on Religious Belief and his Essay in Aid of a Grammar of Assent3. What Newman argues, very roughly, is that many of the reasons people offer in favour of religious scepticism have a tendency to overgeneralise and land us with a scepticism that is far more widespread. The comparison between religious and anti-sceptical convictions is also associated with some of Wittgenstein's epistemological musings in On Certainty4 – something I will return to. At first blush, the parallels really do seem striking. It was also widely thought, once upon a time, that a belief in the existence of the external world might receive a 3 For discussion of John Henry Newman's views on religious epistemology see Kenny (1992, essay 7). 4 Wittgenstein makes no overt remarks about religious belief in On Certainty. But some have taken inspiration from Wittgenstein's notion of a 'hinge proposition' (see remarks 83, 144, 152, 341-344, 558) arguing that a belief in the existence of God, like a belief in the existence of the external world, plays a very different role to familiar everyday beliefs – and, thus, may be exempt from familiar kinds of epistemic evaluation (for discussion see Nielsen, 1967, Phillips, 1993, Pritchard, 2000). There are some suggestions of this kind of view in Wittgenstein's lectures on religious belief (see Wittgenstein, 1966). I will have more to say about this in the next section. 3 purely a priori defence. Few now think that this is possible. And if ordinary people are asked to defend their belief in the external world, more often than not they will produce something empirical – 'Just look around you!' or 'Here's a chair, here's a table'. One might attempt to offer an inference to the best explanation (a rough analogue of an argument from design) – but I shall focus here upon the more kneejerk 'Moorean' type defences. These, in effect, serve as paradigm empirical defences of one's belief. One is after all drawing attention to (mundane) experiences that one has had – experiences that one interprets as providing direct evidence for one's belief in an external world. This, again, runs counter to an idea that is occasionally expressed in epistemology – namely, that belief in an external world is essentially a matter of faith. But now imagine a hypothetical sceptic – a person who genuinely believes that there is no external world. In his view, there are no such things as tables, trees, atoms etc. – all of reality is mind dependent in some relevant sense. (Strictly speaking, this character might be better described as an 'idealist' of some sort, since he actively denies the existence of the external world rather than merely suspending judgment. I shall stick with the term 'sceptic', though – largely to avoid misleading comparisons with subjective or absolute idealism). Such a sceptic would likely remain unmoved by an appeal to perceptual experience – and, it seems, quite rightly so. The sceptic will grant that one has had all kinds of ordinary perceptual experiences – but will simply deny that these experiences provide any evidence for the existence of an external world. For the sceptic, it would be a serious mistake to regard these experiences as caused by extravagant mind-transcendent objects and states of affairs – they will be explicable rather as a kind of spontaneous expression of the mind (one can fill in the details as one likes). The considerations that one cites seem to beg the question against the sceptic – one would not regard these experiences as caused by external states of affairs unless one already believed in the existence of the external world. We are tempted to infer as follows: If a belief in the existence of the external world is based solely upon question-begging grounds, then it is not based upon genuine evidence, in which case it is unjustified. I strongly suspect that defences based upon inference to the best explanation will be question-begging in exactly the same way, but I won't pursue this here. 4 Our first conclusion – that belief in the existence of God is unjustified – would doubtless suit an atheist. But this second conclusion – that belief in the existence of the external world is unjustified – would not suit anyone much. If I am not justified in believing in the existence of the external world, then I plausibly lack justification for believing anything that presupposes it – that I'm currently sitting at a computer, that I'm currently in Scotland, that I have a bruise on my knee etc. And yet the arguments that led us to these two conclusions have an eerie similarity. The argument for religious scepticism, despite appearing quite compelling at first blush, turns out to be in rather bad company. It shares its form with an argument for external world scepticism – an argument that we are going to have to resist in some way or other. In the next section, I shall experiment with a certain strategy for responding to the external world sceptical argument – one that has always struck me as quite appealing – and examine whether it can be extended to the parallel argument for scepticism about the existence of God. II. AN ANTI-SCEPTICAL STRATEGY There is a certain kind of picture according to which the significance of evidence is always transparent in principle to careful, rational inquirers. The idea, more precisely, is that a rational inquirer can always determine, on reflection, whether or not a body of evidence provides genuine support for a proposition. Call this the principle of the transparency of evidence. If this is true, then in any dispute in which the disputants are able to agree upon a shared body of relevant evidence, they should, upon sufficient reflection, also be able to arrive at a shared assessment of what the bearing or significance of that evidence is. There is something very encouraging about this picture, since it looks as though any dispute with this feature could be rationally resolved – at least in principle. Many disputes, however, just don't seem to be like this – and a dispute with a sceptic over the existence of the external world seems like a particularly striking counterexample. Although the sceptic and I can come to agree on what the relevant evidence is – the perceptual experiences that we have both had – we will fundamentally disagree as to what the significance of this evidence is – as to what the 5 evidence shows. He will have his interpretation of the evidence – it reflects the spontaneous activity of the mind – and I will have mine – it reflects the interaction of my perceptual system with external states of affairs. His interpretation of the evidence is backed-up by his belief in a mind-dependent reality and mine is backed up by my belief in the external world. It looks as though we are caught in a kind of circle: We can't settle the question of whether the external world exists without first settling the question of how the relevant evidence is to be interpreted, but we can't settle the question of how the relevant evidence is to be interpreted without first settling the question of whether the external world exists. The dispute being imagined is not simply a dispute over some particular matter of fact – it is a dispute over world-view. Our disagreement is so profound as to leave us with no common ground – in particular, no common ground as to how evidence should be evaluated. We end up with a kind of rational impasse. All that we can say, in the end, is something like this: Provided my belief is true – provided the external world does exist – then there is a wealth of evidence in its favour. The sceptic, in virtue of his strange background doubts, is blinded to the force of this evidence. Unless he relinquishes these doubts it will remain opaque to him. My inability to persuade the sceptic is just a reflection on him and his strange background doubts – it does not impugn my evidence or my belief. There is, of course, another side to this: In the event that the sceptic is right – that reality is mind dependent – then there is no evidence whatsoever for believing in the existence of the external world. I would be the one misinterpreting the significance of perceptual experience – and doing so, seemingly, as a result of a dogmatic background belief. We might say that a belief in the existence of the external world 'looks after itself' – if it is true, then there will be a wealth of evidence in its favour, and it will turn out to be thoroughly justified. Believing in the existence of the external world, then, is not a matter of faith – in one sense, the very opposite is true. Believing in the existence of the external world commits one to regarding the belief as supported by a torrent of evidence. 6 The sceptical argument outlined in the first section traded upon the plausiblesounding assumption that question-begging grounds could never constitute genuine evidence in favour of a belief. We can now see, though, that the assumption is suspect – it trades upon the principle of the transparency of evidence. Just because the sceptic is unable to appreciate the significance of my evidence for the external world doesn't mean that it isn't real evidence. The significance of evidence is not transparent – we should not always expect an individual with bizarre background beliefs and doubts, such as an external world sceptic, to be in a position to appreciate it. While it may be generally true that question-begging grounds do not constitute genuine evidence for a belief, this will not be so for the special case of beliefs that condition our very attitude toward evidence of certain kinds. In particular, it will not be so for a belief in the existence of the external world. We have, then, a certain response to the external world sceptical argument of section one and a kind of antisceptical reassurance. This is not the sort of reassurance that Descartes was after of course. If we allow ourselves to first doubt the existence of the external world, then the assurance is no longer available to us. But it does offer reassurance to those who are convinced that the external world exists – the justificatory status of the belief will be ensured by the very world-view that it enshrines. Do these considerations generalise to a belief in the existence of God? It is easy to imagine that a dispute over the existence of God could bog down in exactly the same way as a dispute over the existence of the external world. Both theist and atheist can acknowledge that the theist's religious experiences constitute relevant evidence – it's just that they will profoundly disagree as to what this evidence shows. For the theist, these experiences are a direct result of God's agency. For the atheist, they result from wish fulfilment, insecurity, delusion etc. Once again, these divergent interpretations of the evidence just seem to be part and parcel of the two respective world views, in which case it is unclear how any rational progress might be made. Could belief in the existence of God 'look after itself' in the same way that belief in the existence of the external world does? While I have been talking rather nonchalantly up to this point about 'belief in the existence of God', it is quite clear 7 that different people can mean very different things by professing such a belief. That is, there are many different ways of conceiving of the nature of God and His relationship to human beings – many different kinds of religious world view. One conception of God that is prominent in philosophical discussions is the so-called Judaeo-Christian conception, which emphasises divine attributes such as omnipotence, omniscience and omnibenevolence (I myself am somewhat unsure as to the extent to which such attributes actually feature in ordinary religious convictions). In any case, what appears to be crucial in determining whether one's religious world view looks after itself is whether one's conception of God builds in sufficient details of how His properties, attitudes, wishes, plans etc. are disclosed to believers – in the same way that our conception of the external world builds in the idea that its features are disclosed in perception. It is the mere possibility of such a conception that strikes me as significant, at least in the present context – and the possibility of augmenting or extending a conception of God in the required manner5. Given such a conception, we have a 5 Whether actual religious convictions have this feature is an interesting question. I suspect that the answer is yes – though I don't intend to pursue this matter in any depth here. Prominent in John Calvin's influential conception of God and his relationship to humankind is the notion of a sensus divinitatis – a kind of innate human faculty, the express purpose of which is to deliver knowledge of God. As he writes: There is within the human mind, and indeed by natural instinct, an awareness of divinity...To prevent anyone from taking refuge in the pretense of ignorance, God himself has implanted in all men a certain understanding of his divine majesty...' (Calvin, 1559, I, iii) This might be thought to enshrine a religious world view that itself makes provision for the sound provenance of religious beliefs. Calvin himself takes inspiration from the following passage from Romans I: For the wrath of God is revealed from heaven against all ungodliness and wickedness of men who by their wickedness suppress the truth. For what can be known about God is plain to them, because God has shown it to them. Ever since the creation of the world his invisible nature, his eternal power and deity has been clearly perceived in the things that have been made. So they are without excuse... (Romans I: 18-20) For further discussion of the sensus divinitatis see Plantinga (2000, partic. chap. 6). John Henry Newman is also quite clear in regarding (Christian) religious belief as pertaining, in part, to its own rational justification. He writes, of Christianity: ...reason [need not] come first and faith second (though this is the logical order) but one and the same teaching is, in different aspects, both object and proof, and elicits one complex act both of inference and assent. (Newman, 1870, pp316) 8 response to the religious-sceptical argument offered in section one and a certain kind of anti-sceptical reassurance. Once again, though, this reassurance is limited to those who are firm in their religious convictions – and, importantly, unavailable to those who are already gripped by doubt over the existence of God. This, of course, is not the only anti-sceptical strategy that we might adopt. One very influential alternative – to which I now turn – is that canvassed by Wittgenstein in On Certainty. The rough thought behind the Wittgensteinian approach is something like this: Inquiry has to stop somewhere. If we are to conduct inquiry at all, then we must be content to accept certain things without inquiring into them. To put it slightly differently, in order for our practice of doubting and accepting things to get off the ground, certain things – so called 'hinge propositions' – must be exempt from doubt. As Wittgenstein writes: ...the questions that we raise and our doubts depend upon the fact that some propositions are exempt from doubt, are as it were like hinges on which those turn. That is to say, it belongs to the logic of our scientific investigations that some things are in deed not doubted. (Wittgenstein, 1969, sections 341-342) If a proposition supports or undergirds our practice of inquiry in this way then, so the thought continues, it can be accepted without the need for evidential support. Believing a hinge proposition can be in epistemically good order purely in virtue of the pivotal role that the proposition plays 6 . The Wittgensteinian rejects the 'evidentialist' thesis that beliefs can only be justified if they are grounded in evidence – beliefs that play the right sort of supporting or enabling role can be exempt from this requirement. A belief in the existence of the external world presumably plays this kind of role vis a vis ordinary empirical inquiry. And there is good reason to think that this broad kind of anti-sceptical strategy could also be applied to a belief in the existence 6 This anti-sceptical strategy is sometimes supplemented by a semantic claim to the effect that hinge propositions are not 'fact-stating' or don't serve to 'describe the world' – a thought that is supposed to make the prospect of accepting them without evidence more palatable. This is, roughly, the approach pursued by Phillips (1993) and Wright (1985) and strongly suggested by some of Wittgenstein's own remarks (see for instance, 205, 214, 215, 308, 309). Interestingly, this kind of idea would have no obvious role to play when it comes to the anti-sceptical strategy that I'm advocating – on the contrary, it would seem to sit rather uneasily with it. I won't explore this further here. For more general discussion of the Wittgensteinian anti-sceptical strategy see Pritchard (2000) and Wright (2004). 9 of God. One would simply need to make the case that such a belief plays a similar pivotal role with respect to a practice of inquiry – namely, religious inquiry (inquiry into God's nature, plan etc.) (see Pritchard, 2000). For the atheist, of course, such an inquiry will be completely misguided from the start – but then the external world sceptic would have a similar attitude towards ordinary empirical inquiry. My own anti-sceptical strategy has some similarities with the Wittgensteinian approach – but some important differences as well. The Wittgensteinian holds that, if inquiry is to get started, certain things just have to be taken on faith and, thus, it can be epistemically appropriate to do so. And yet, as I've argued, it is wrong to conceive of our belief in the existence of the external world as a matter of faith – ordinary believers would not see it this way. If faith be understood as a self-conscious willingness to believe in the absence of evidence, then I am unsure whether anything needs to be accepted on faith and, further, whether it could ever be epistemically appropriate to do so. Given that a belief in the existence of an external world is based solely upon grounds that would beg the question against a sceptic it is a two-step inference to the conclusion that the belief is unjustified. From the fact that the belief is based solely upon question begging grounds, we infer that it is not based upon genuine evidence and from the fact that it is not based upon genuine evidence, we infer that it is not justified. The Wittgensteinian rejects the second step – for him, the fact that a belief is not based upon evidence does not entail that it is unjustified. I, on the other hand, am inclined to reject the first – for me, the fact that a belief is based upon questionbegging grounds does not entail that it is not based upon evidence. III. MAINTAINING ONE'S CONVICTIONS What, then, has been accomplished so far? I have certainly not shown that belief in the existence of God is justified – or even that belief in the existence of the external world is justified. I have, though, deflected a certain kind of argument against both claims. If the foregoing reasoning is correct, I have established something conditional: If there is an external world then belief in the external world is justified. If there is a God, then belief in God is justified (for a suitable conception of God). Of course, 10 there is no material here to persuade or even trouble an atheist. If this conditional is true, though, it does hold a lesson for the theist – particularly regarding the conditions under which he might be rationally obliged to relinquish his belief. To put it slightly differently, there are no resources here for a theist who is interested in the evangelical project of spreading his religious beliefs to other people, but there is some reassurance for the (perhaps less self-possessed) theist who is interested in an altogether more personal project: reconciling his religious beliefs within his own mind, when confronted with various kinds of criticism. In this final section I will briefly explore the nature of this reassurance. We can in general distinguish two different ways of criticising a belief – two different strategies that we might adopt in trying to persuade someone to give up a belief. The first is the direct approach – we argue that the belief in question is false. Call this the de facto strategy. The second strategy is indirect – we argue that the belief in question is unjustified or irrational, whilst remaining neutral on whether or not it is true. This second approach may be particularly common as a fallback, when debate over the truth of a belief has, for some reason, bogged down. Call this the de jure strategy (see Plantinga, 1998, 2000, partic. the preface). Many of the most famous – and, I think, influential critiques of belief in God fall into the de jure category. Freud famously argued that religious belief arose through a mechanism of wish-fulfilment – when the terrifying helplessness that besets us as children lingers on into adulthood, according to Freud, we are inclined to seek out a replacement for the father figure that once provided comfort and security. Marx regarded religious belief as a kind of delusion produced in individuals by a malfunctioning political and economic system. Nietzsche held that religious belief originated from a kind of resentment on the part of the oppressed – and served to reinforce and legitimate a weak, though self-righteous, character7. These criticisms do not engage with the question of whether or not religious beliefs are true as such – they aim to show, amongst other things, that such beliefs have a dubious and unreliable provenance of one sort or another. 7 Freud's views on religious belief can be found in his The Future of an Illusion and Marx's can be found in his On Religion (with F. Engels). Nietzsche discusses the origins of religion in On the Genealogy of Morals, amongst other places. 11 Putting these more sophisticated critiques aside, a very common, everyday way of criticising religious believers is to allege that they lack evidence for their convictions. It is easy to see why this kind of strategy might be attractive. It enables us to bracket metaphysical or ontological issues and focus in upon epistemological ones that seem at once more mundane and tractable. If the reflections of the previous two sections are on the right track, however, then a purely de jure criticism of belief in God is actually impossible. One cannot attack the justificatory status of belief in God, whilst remaining neutral on its truth – for the two are intimately intertwined. If one believes in God then one will take there to be ample evidence supporting His existence. A belief in the existence of God, like a belief in the existence of the external world, conditions one's overall view of reality and one's view of what sort of beings we are and what kind of place in the world we occupy. Religious belief, if true, will be justified. Thus, there is no way of arguing about the justificatory status of religious belief while suspending the question of its truth. For most beliefs it makes perfect sense to separate out the de facto and de jure strategies. Suppose I'm trying to comfort a paranoid friend who is convinced that his wife has been unfaithful. If I don't have any direct evidence regarding her fidelity, it would make a lot of sense for me to abandon the direct de facto strategy and opt for a de jure strategy instead. Or suppose I am arguing with someone who believes that the world is flat. If he is unimpressed by the evidence that I produce (he thinks satellite photographs etc. are all faked), I might well try a different tack and opt for a de jure strategy. This would, in effect, flip the dialectical onus – it would then be his turn to produce putative evidence and my turn to challenge it. In both cases the de jure strategy might well meet with greater success. But belief in the existence of God is unusual in this respect – a feature I take it to share with belief in the existence of the external world. In this case, the de jure strategy will end up implicating the very de facto dispute from which we were trying to escape. The distinction between de facto and de jure criticisms of religious belief is discussed in detail by Alvin Plantinga (2000), who draws essentially the same conclusion as I do: There is no such thing as a pure de jure criticism of religious belief 12 – if religious belief is true, then it will be justified. Plantinga, though, arrives at this conclusion via a somewhat different route. One way to ensure that this conditional holds is to tailor the consequent – to motivate a conducive analysis of epistemic justification. This is roughly the strategy pursued by Plantinga. Another way to ensure that this conditional holds is to tailor the antecedent – to build more content into the religious beliefs themselves. This is roughly the strategy that I have pursued. To put things slightly differently, Plantinga brings the justificatory status of religious belief into conformity with its truth, while I bring the truth of religious belief into conformity with its justificatory status. I've defended no specific account of epistemic justification or evidential support and, as far as I can tell, my reasoning will be compatible with a number of different ways of thinking about such topics. When considering Plantinga's view, there is one further complication worth noting here: What Plantinga strictly argues in chapter six of Warranted Christian Belief is that religious belief will be warranted if true. The terms 'warrant' and 'justification' are sometimes used interchangeably – but this is more than just a terminological difference. Plantinga uses 'warrant' as a semi-technical term meaning 'that quality or quantity ...whatever it may be, enough of which distinguishes knowledge from true belief' (Plantinga, 2000, pp153). When it comes to the ordinary notion of justification, Plantinga appears to hold that religious belief is or can be justified, irrespective of whether it's true – a contention of which I am somewhat doubtful. I won't explore Plantinga's views any further here. When W.K. Clifford famously proclaimed 'it is wrong always, everywhere and for anyone to believe anything upon insufficient evidence', he had religious believers squarely in his sights (Clifford, 1879). And yet, if the view I am defending is along the right track, then religious believers have nothing to fear from Clifford's proclamation – religious beliefs need never exceed the authority of available evidence, at least when evaluated from the believer's own perspective. Religious belief would, no doubt, exceed the authority of available evidence as Clifford is inclined to evaluate it – but that hardly need trouble a religious believer. There are, to be sure, truths about what provides evidence for what, about what a person's evidence genuinely supports etc., but they are not branded onto the minds of all rational inquirers. 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