Flashback #1.

One of the things I plan to do with this blog is to put up some of the things I have written in the past, which are currently distributed as notepad files across at least 3 computers, so as to have them all at my fingertips wherever I go. Since one such item is linked to my loss of faith, this seems a sensible time to post it. It's a slightly modified version of an email I sent to a friend last Christmas explaining some of the aspects of Christianity that I have trouble with.

The first issue is one of evidence. I don't mean to deny that there is evidence for Christianity, but to claim that what evidence there is is extremely weak. A major theme of this weakness is the existence of reasonable alternative explanations.

A characteristic example is personal spiritual experience. It is an interesting fact that most people at some point have a compelling sense that there is something greater than themselves, and that this often happens in a religious context. The powerful and mind-enveloping nature of these experiences means that not only their inherent interest but also the experiences themselves demand (and often suggest) an explanation. Such experiences are often taken to be evidence of Christianity: They may be described, for example, as 'a sense of the presence of God'. Typically, it is not the fact that many people have had such experiences which is used as evidence. Instead, many people are persuaded of the truth of Christianity partly on the basis of their own personal experiences.

The weak point of such evidence is the availability of alternative explanations. The physiology of such experiences has been studied, and purely physical mechanisms have been suggested. The idea is not too complicated: Not all parts or states of the brain have the function of directly determining the nature of the world. For example, although we dream when we are asleep, and the dreams themselves are mind-enveloping, we do not afterwards think that the reality suggested by dreams is in any sense true. It is reasonable to suppose that mystical experiences are similar; they are a state of the brain produced by factors in the real world other than the ones that they immediately suggest. This is backed up by the fact that they can be produced by epilepsy, by certain drugs, and (to a lesser extent) by particular frequencies of infrasound and certain kinds of architecture.

Another typical feature of this kind of evidence is that it is necessary even for those who use it to admit that there must be alternative explanations. Mystical experiences are not limited to Christians, or even to theists. A Christian and an agnostic have the same difficulty in explaining the deep spiritual experiences of Muslims or Buddhists. The explanation that this is God revealing Himself to them is open to the objection that he is doing so in a distinctly deceptive manner. On the other hand, the more typical (physiological or diabolical) explanations remove the value of the original evidence for Christianity: My own spiritual experiences are as likely to have a physiological or diabolical cause as those of other people.

The point of this is not just to undermine the argument from spiritual experience, but more generally to illustrate the kind of weakness posessed by many of the usual things cited as evidence for Christianity, such as the Bible, other reports of miracles, the existence and rapid initial growth of the Church etc. This argument is in no way intended to demonstrate the falsity of Christianity: Indeed, no argument of this kind could ever do more than undermine particular arguments for Christianity. But if all arguments and evidences for Christianity may be countered in this way, that is a real issue.

To make the point more vividly, imagine that the claim 'We don't have conclusive proof of the existence of aliens because they have the technology to carefully observe us without revealing themselves' is true. (Warning: In what follows I don't intend to draw an analogy between aliens and God. That is a different thought-experiment). Suppose further that the alien observers have only recently arrived, that they are extremely intelligent, and that they are able to gather physical information about us at any level of detail they wish. In particular, they have access to all current documents including the Bible, the Qur'an and so on. Would they come to the conclusion that Christianity is true? If so, on what grounds might they do so?

This issue can also be approached from a more philosophical angle. Some statements are generally accepted as either true or false. Others, such as 'if when scampi green', are exempted from this distinction, and declared meaningless. Some examples are less obvious. For example, in the middle of the last century two different interpretations of quantum mechanics were devised. The first (the 'many worlds' interpretation) states that all the time, all over the place, the world is 'branching' into different worlds, and that everything that could happen, actually happens in some possible branch. According to this theory, the reason why we don't experience the world as branching in this way is that we ourselves do the same thing. Any particular branch of you only has memories and experiences within their own branch; the different events in different branches are experienced by different versions of you. This is an extremely strange theory, but it has experimental backing. The second (the Copenhagen interpretation) says that there is no such thing as a real world made up of particles in particular places moving at particular speed. Instead, the world is a 'superposition' (a kind of funny mixture) of such worlds. However, if you make any measurement at all, then the world mysteriously changes and becomes a mixture in which the experiment you performed (and no other) has a definite outcome. So no experiment can produce a funny mixture of results reflecting the funny mixture that the world 'really' is. This is also an extremely strange theory, and this also has experimental backing.

The odd thing is that the experimental backing of the two theories is exactly the same. Indeed, if you work through the mathematics you find that these two totally different theories make precisely the same predictions. That is, any experiment that supports either must support both, and vice-versa. So it is not clear what to do with statements like 'it is the copenhagen interpretation, and not the many worlds interpretation, which is correct'. The universe behaves just the same way whichever way you do the mathematics, and it seems odd to pick out one way of making the same predictions as true, and the the other as false. This is an area in which objective notions of truth are on shaky ground. But if there is no way to distinguish Christianity from the alternative explanations given for the evidence, then statements like 'The claims of Christianity are true' end up on similar ground. If there is no experiment we can perform to demonstrate, for example, that God answers prayer (and there is no experiment we can perform to show that He does not), then statements like 'God answers prayer' are in this sense meaningless.

One of the most obvious objections to this line of thinking is that there is an experiment that I can perform to determine whether such statements are true. All I have to do is wait. Eventually, I'll die, and then, if the claims of Christianity are true, I'll know it. This objection could be caricatured as 'Evidence? You want evidence? Well, you'll get evidence. Plenty of evidence. But by then it will be too late.'

The main problem with this objection is that it relies fundamentally on the person who faces God after death being me; that is, being the same person who is currently writing this email. This brings me to the second issue, which has to do with the Christian account of the self.

It is necessary at this point to indulge in a little pedantry. When I used the word 'me' to refer to 'the person who is currently writing this email', I was referring not to myself over all time, but only over a very short period of time, in which it is obvious what it means to say that I remain the same person. That is, I was referring to an instance of myself. There doesn't seem to be a word that summarises the idea of a person-instance in this sense, and I shall want to refer to this concept quite a bit. So, from now on I shall use the word 'being' to mean what I would otherwise have to summarise by the phrase 'person-instance'.

The point is that the objection above relies fundamentally on the idea that two beings (me and a particular being who God ultimately judges) correspond. The normal account of this (indeed, it is so commonly assumed that it is fundamental to the language; hence the pedantic paragraph above) is that the way these two beings correspond is via a person, or self, of which both are instances. More generally, it is assumed that we have a way to assign each being a person (of which that being is said to be an instance) in such a way that two beings correspond if and only if they are instances of the same person. Picking out a correspondence of beings over a short period of time is usually quite easy; after all, over such short periods each being is associated to a body, and the bodies remain quite stable over these short periods. By extending the correspondences this gives us, we get a way to identify beings which, in most normal circumstances, really does allow us to associate lots of beings together as instances of a person. Thus, for example, I can be identified as an instance of the same person as a particular baby born 23 and a bit years ago.

But this simple way to find a correspondence between beings cannot be all that we mean when we talk about selves. After all, hundreds of millions of people believe in reincarnation: That is, that particular beings alive today are instances of the self-same people as other beings who died many years ago. This identification is not made by the process described above. Similarly, as mentioned above, Christian doctrine relies on a similarly extrapolation of the notion of a person. But the very notion of people breaks down when faced with a simple thought-experiment.

Imagine yourself in a sci-fi world where there is a civilisation on the moon. Imagine further that the normal way for people to get to the moon is via the port-o-matic teleportation device. You go into a small room, close the door, and press the magic button. But when you open the door, hoping to greet your smiling lunar friends, you find that you are still on Earth. The explanation is obvious: The teleporter has malfunctioned. But now suppose that the malfunction was not in failing to produce a copy of you on the moon, but in failing to destroy the copy left on earth. That is, there are now two beings who might sensibly be described as being you; call them Matt1 (on Earth) and Matt2 (on the moon). Actually, this may not be the right way to put it: We want to say that the beings Matt1 and Matt2 are both the instances of the same person as the being Matt, who walked into the teleporter. But equally, we want to say that Matt1 and Matt2 are now instances of different people. There is no way to assign people to Matt, Matt1 and Matt2 that meets these conditions.

I'm sure you have seen thought-experiments of this type, and that you could concoct more complicated or striking examples in which, perhaps, Matt1 remains a Christian but Matt2 apostatises. But there is no need to picture such a fantasy world to get at this phenomenon. It is already with us, in split-brain patients. There is no consistent way to assign these beings as people. The Christian account of the world relies strongly on the identification of beings consistently into people: Each person is supposed to persist eternally in heaven or hell, for example. The beings in heaven and hell are very different to those they are associated to on Earth. Those in heaven are perfectly good, and those in hell are perfectly evil. On the other hand, some of the beings on Earth are pretty mixed. So it is not clear which beings on Earth are to correspond to which after death. That those after death may have memories of particular lives on Earth is one possibility, but memories are flimsy things and consideration of people with total memory loss suggests that memory should not be essential to the self. The issue is particularly confused by people whose personalities are totally changed by severe brain injuries, and by those with severe dementia.

This issue may well become more clear-cut within our lifetimes. Scenarios such as those in the thought-experiment may become practical. Artificial intelligence may finally be accomplished. Or possibly scientists will discover that these scenarios are impossible, because something inside each normal human brain does not obey the laws of physics. This would correspond to the discovery that we have non-physical souls, would resolve all of these issues in favour of the religious view, and would be hugely surprising for scientists everywhere.

The third and final issue relates to the Big Questions, those which have no generally accepted answers today, despite having been studied by brilliant thinkers for thousands of years.

Traditionally, it has been claimed that religions such as Christianity provide answers to these Questions, but it is not clear that they do. Very often, the answers beg the question, by postulating some aspect of God to which the same Question still applies. A classic example is the Question 'Why is there anything at all, rather than nothing?'. Initially, it looks like this Question is answered by Genesis 1:1; The reason why there is anything at all is that it was created by God. But this begs the question; after all, God is Himself supposed to be something, and the Question 'why is there anything at all, rather than nothing?' applies equally to God as to the created universe.

Similar remarks apply to Questions about the nature of things, such as 'Why does what there is behave in a regular fashion?', or 'What is the purpose of everything?'. Another interesting example is the Question 'Why are there so many simple Questions that we don't know the answers to?' Each such Question corresponds to an attribute of God. The fact that we do not know the answers to the Questions applied to those attributes is called the ineffability of those attributes of God. So this Question corresponds to the idea that the ineffability of God is itself an ineffable attribute.

C.S. Lewis said 'I believe in Christianity as I believe that the sun has risen: not only because I see it, but because by it I see everything else'. Here he is referring to the explanatory power of Christianity. This explanatory power is usually taken to lie in the light shed on the Big Questions by Christian doctrine (after all, smaller questions may be left to science, history, geography, mathematics, common sense etc.). But all that the standard answers to these Questions do is to pull them back to a different level; the same Question, asked at the new level, is answered by the statement that God is ineffable. But this is no answer at all, and certainly isn't a satisfying explanation. In this way, much of the supposed explanatory power of Christianity is nullified.