My routine trips to the doctor’s surgery (blood pressure, statins etc.) are predictable, as is the reading material in the waiting area –  fascinating health advice leaflets plus old magazines. Foraging on a recent visit, though, unearthed an eighteen-month old New Scientist with the cover story “What We’ll Never Know”.
Which of course set me off once again contemplating science, knowledge, religious experience and so on.

First was a quote from Martin Rees, the Astronomer Royal, pointing out that chimpanzees do not understand quantum theory – but, in addition, they do not realise that there is any such thing to understand. Likewise, there may be aspects of the universe to which we are oblivious. There is no reason to suppose that our brains are made to understand every level of reality. I would add that even if they were, it is difficult to see how we could prove that point.

The next concern of the writer (Michael Brooks) is the Heisenberg uncertainty principle – that we cannot know with certainty various features of sub-atomic particles. The act of observation alters what we observe. This is followed up by mention of Gödel’s Incompleteness Theorem which deals with the fact that mathematical systems cannot prove themselves to be true. I have never understood this, but Brook gives the helpful example of arithmetic. The axioms of arithmetic cannot be proven by arithmetic. Any mathematical theory of everything is therefore bound to be lacking in final proof.

Next in the firing line is biology. According to Jerry Coyne, of the University of Chicago, we can never know for sure how life got started. Molecules don’t get fossilised like animals and plants, so we have to rely on simulation in the laboratory. But this can only tell us what might have happened, until such time (I suppose) as we can simulate a hefty chunk of planet at very high temperatures and with very specific chemical and geological features. That seems a long way off.

Another biological conundrum is the nature of consciousness. Russell Stannard of the Open University thinks that it may well be the case that consciousness is beyond our understanding. Daniel Dennett, of course, famously disagrees. He is certainly a ‘glass half full’ person but his optimism does not convince everyone. And he is a philosopher, not a scientist.

Talking of theories of everything, most of those who take an interest in the subject are probably aware that the entities proposed by string theory and its offshoots are unbelievably small, even by the standards of the sub-atomic world. Michael Brooks points out a less well-known result of this tiny scale, which is that in order to learn more about these entities we would need the use of a particle accelerator the size of the universe. The LHC is reduced to the functionality of a pea-shooter in this Lilliputian world.

Brooks is careful, rightly, to reflect on the success of science. In fact, one of the paradoxes of the whole thing is that recognising what we cannot know has generally resulted in an increase in our actual knowledge. It seems to me that this applies particularly in those cases where our lack of knowledge is inherent – the references to Heisenberg, Gödel and Stannard fit within this category. Our understanding of quantum theory, mathematics and the functioning of the mind has progressed, even though we cannot grasp the underlying reality.

This inherent unknowability is different from the sort that arises because we don’t have a big enough chemistry set to simulate the origins of life, or a big enough LHC to test out string theory. Those issues can be tackled in principle, even if not in practice, whereas inherent mystery cannot be tackled at all. It just is.

It appears that there is a meeting point here between science and religion. Both point to ultimate mystery. The fascinating question is, ‘Can they therefore talk usefully to each other about mystery?’ I think they probably can – but there is an important proviso on each side.

From the religious perspective, there should be no ‘God of the gaps’ thinking in which God is wheeled in to fill gaps in scientific understanding. Thankfully, this is now a minority attitude except among some fundamentalists. Almost invariably the anti-religious, especially the ‘new atheists’, take this as a basic tenet of all religion, which it is not.

Equally, there should be no ‘science of the gaps’ thinking,  in which science is brought in to explain gaps in religious understanding. No matter how deep our faith, we can probably never fully understand human nature, the existence of suffering, or the ultimate purpose of the universe. Yet Dennett and his like-minded colleagues are always ready to step in with scientific ‘explanations’ – and sometimes romantic sci-fi speculation – to fill that kind of gap.

I may, of course, be accused of bias, but I believe we have passed a tipping point. Gap thinking has become more common within science, at least at the popular level, than within religion.

Perhaps we should all start again.