Cosmology, the structure of science, and meaning, LMH Oxford 05/16
Sermon in Lady Margaret Hall chapel, 1st May 2016
I am a professor of physics at this university, and in my considered opinion there is good reason to think that on April 5th in the year 33 AD in Jerusalem a jewish Rabbi named Yeshua, and given the title Christus by his pupils, was raised to new and fuller life after he had been executed and dead for two nights.
I have been asked by Dr Doig to begin a series of sermons in the area of science and Christian commitment. This is a rich subject, so I will have to be selective. Since my own expertise is in the area of fundamental physics, I will discuss two things where that expertise is relevant. The first is physical cosmology. The second is the structure of scientific explanation.
Let me say at the outset that there is absolutely no contradiction whatsoever between the fruits of mainstream scientific study of the natural world, and the opinion that the world has its origin and purpose in a grand act of loving creativity.
That was a long sentence, so let me say it again:
there is absolutely no contradiction whatsoever between the fruits of mainstream scientific study of the natural world, and the opinion that the world has its origin and purpose in a grand act of loving creativity.
There is tension, but not contradiction. The tension is owing to the fact that the world is both beautiful and ugly at the same time. The world is shot through with pattern and beauty at every scale, and yet right in that pattern and beauty there is also appalling pain, ugliness and suffering. When we assert Christian commitment we are not asserting that the world is completely beautiful. We are asserting that truth, goodness and beauty are to be sought and can be found, right in the middle of the pain of the world. Yes, even in a situation of disownment, public humiliation and torture, meaning can be expressed by us if we so choose.
I mentioned that lovely trinity of truth, goodness and beauty just now. I have not yet mentioned the word ‘God’. This is because that word is commonly misunderstood, and I think I am speaking to a partly atheist audience. My experience of modern-day atheism is that the versions of ‘God’ that it mostly rejects are versions that no thoughtful theist believes either. I don’t think there is some sort of vast supernatural being sitting in a parallel dimension and playing mind-games with us, and I don’t think Jesus of Nazareth thought that either. The word ‘God’, for a thoughtful follower of Jesus, functions quite similarly to the word ‘truth’ in everyday language. It is simply that we think the nature of truth is rich and deep, and extends to all aspects of our experience, and ultimately truth is about love, and God is love.
I learned of a woman living in North Oxford who, meeting a clergyman, ventured to say that she did not believe in God because she believed in Darwinian evolution. That is like saying you don’t like truth because you prefer facts. It has the same logic as the statement that you reject maths because you embrace arithmetic. In other words, it has no logic at all. But what is bizarre about the situation is that that woman probably considered herself to be intelligent and well-informed.
I expect the clergyman was at a loss to know what to say. The problem is that such a woman is misusing the word ‘God’. She probably has little idea what that word means when it is used thoughtfully. What it actually means is the absolute reality that we slowly come to know as we learn better who we are. Such learning involves and includes to take seriously the natural world that God brought about and cares about. Therefore we both accept and indeed rejoice in its evolutionary history, especially in view of the fact that there is so much improvisation and trial and error in that beautiful story.
Let’s come now to the subject of cosmology.
The observable physical universe has in it some 500 billion galaxies, each containing of the order of one hundred billion stars. There may be more universe beyond what is detectable from Earth, and ultimately it is impossible to know whether or not the universe is infinite, but infinity seems a bit big to me so I suspect that it is finite. Anyway it is certainly huge. The universe is also ancient, but not infinitely ancient. It has developed from an early state in which it had little explicit structure but vast amounts of hidden structure. This early state was extremely hot and dense, something like a boiling soup or a sort of primordial ocean of fundamental fields, about 13.82 billion years ago.
Looking intensely into the nature of all this structure, and what supports it, modern physical cosmology has become quite precise, and one of the chief things we find about the universe is that it is exquisitely sculpted and balanced. I say exquisite because there is a lot of structure in the patterns that we call “laws of nature”, and these patterns are finely balanced, in the sense that the tiniest change in them would change the universe so completely that it certainly could not support life.
What should we make of this exquisitely balanced pattern? This is an ongoing puzzle, and I don’t want to deduce from it more than is warranted. One well-warranted thought, however, is the following. It does not look as though the basic patterns of the universe can be explained by mathematical physics alone. The mathematics of string theory, for example, is rich enough to describe many types of universe, and the reason why we have the one we have almost certainly cannot be found there.
This issue acts as a sort of nudge towards other territory. It acts as an invitation to explore. Could the reason for the universe lie at some other level of explanation, not mathematical, but artistic, perhaps, or perhaps in a mode of being, of da-sein, that we only ever reach towards and imperfectly express?
Let me admit that physical cosmology does not guarantee theistic conclusions. The cosmic Big Bang does not itself imply a transcendent Creator who can care about what came to be. But physics does hold out an invitation to explore further, because the sort of maths that we find there leaves lots of open questions. It is a bit as though we had discovered the notes of the musical scale and some basic principles of harmony, but those principles are not themselves enough to capture what is going on in the work of Mozart or Beethoven.
To summarize so far, there is good reason to trust that God is love, but that reason cannot come from study of basic physics. Rather, physics leaves the issue open, and cosmology is one strand in a larger framework which together invites us to lift up our hearts to God.
Before leaving this area, I think I may be able to help with one issue that bothers many people, and that bugged me in the past.
Here it is.
In view of the vastness of the cosmos, is it reasonable to suppose that any Originator or Supporter of that vastness would be particularly interested in, or concerned about, affairs on planet Earth? Our Sun is just an ordinary star, after all. Our planet is just one mote of dust among a billion billion others. Isn’t it unreasonable to suppose that anyone with a cosmic vision would care about us?
To answer this, I offer three strands of argument. The strands are in the areas of scientific enquiry, justice and compassion.
First, scientific enquiry. It is in fact the case that Earth is special because it has life on it and most planets do not. Of course I admit that many other planets in the universe may also harbour life; my point is simply that any that do are a legitimate focus of interest over and above those that don’t.
Next, justice. It is a fundamental principle of justice that everyone be treated equally. Just because planet Earth is ordinary in many respects, that does not imply that injustices done here should be ignored or treated as any less important than any other injustice.
Finally, compassion. Compassion gathers where it is needed. Love is drawn to the supposedly insignificant and asserts significance.
Altogether then, it is quite reasonable and not at all pompous to suppose that human affairs matter to God. The attempt to deny this is not humility, but a form of false humility or untruthfulness. Or maybe the idea that you and I do not matter to God is simply an easily forgivable ignorance.
I will turn now to my second main point, which concerns the structure of scientific explanation in general.
There is a widely held view that I want to question. This is the view that it cannot in the end make any sense to trust that ultimate truth is love, because love is complicated and the universe must ultimately be explained in terms of simple things. This argument has the appearance of logic, or of science, but I want to show that it is in fact muddled because it makes a category error.
This argument suggests that all physical phenomena are the outworking of impersonal laws, and that is all. It is claimed, in short, that the notion that loving purpose is the grand narrative of the natural world does not make any sort of scientific sense.
Let me say that I have very much sympathy with anyone wrestling with this idea. The way science is commonly presented nowadays does make it hard to see why this idea is wrong. And the issue is subtle, so that in the time I have now I cannot unpack it in full. I will simply offer some very brief pointers, and encourage you to explore further.
For my first pointer, I note that the structure of scientific explanation is two-way not one-way. By this I mean that physics and biology, for example, both contribute to a full understanding, and each illuminates the other. It is not true that physics is all we really need, and biology is a form of stamp collecting. In fact, the study of biology yields vast amounts of insight that illuminates physics, because it shows what physical things are capable of.
The situation is similar to structure of a large building. Suppose that someone wants to know why the roof of the cathedral does not fall down. One could show them all the stones and the mortar between the stones. These are piled up, one of top of the other, and they support the roof, and this is a complete account. There is nothing else. Stones and mortar are all you need to give a complete explanation. Or so it would seem.
But now someone else comes along and, looking up, they don’t notice the stones in the first instance. What they see are pillars and arches, and walls and buttresses. So they explain that the roof is held up by these structures, by the arches and pillars and so on. It doesn’t particularly matter what the pillars are made of. So now it looks as though the stones and mortar are a mere after-thought. The stones have a role to play, but the heart of the matter is the strong shapes such as pillars and arches.
I hope you get the point. Which is more important? Physics or biology? Stones or arches? In fact, both layers of explanation contribute, and neither explains the other. Here is the central point: an arch is not explained by a stone. An arch doesn’t even need to be made of stones, because it could be made of wood or some other material. So an arch is not explained by stones. Rather, an arch shows one thing that groups of stones can do.
Once we get a good grasp of the structure of science, we find that it fully embraces the notion of layers of meaning, and furthermore it naturally suggests that there may be further layers of meaning beyond the ones that it directly describes. Obviously, science can’t prove this. It can only suggest it. But that is what it does suggest.
It would take much longer to argue this in full, of course. But I want to emphasize, in all honesty, that this really is the truth of what science is like, and I am not ignorant about this. In chapel we are not playing games. We are speaking the truth as clearly as we can. The truth of the situation is not what you may have read in New Scientist magazine, or in hasty and misleading works of popular science, no matter how eloquent or prestigious their authors.
An intelligent religious faith is not an alternative to science, nor is it at odds with science, but in fact it gets science right, and also makes a reasonable venture into the arts and humanities.
And, of course, faith explores further still. To trust in God is to be willing to recognize that our encounter with truth can, in the end, be a personal encounter. By ’personal’ here I don’t mean anthropomorphic; I mean capable of intimacy and shared endeavour. That is the sense in which God is personal.
I will now have to skip some material; I will proceed straight to my conclusion.
So let me finish with a few thoughts on how this works out in practice.
God is recognized and encountered mostly through ordinary facts and natural happenings. He is encountered mostly in the everyday, seen fully. God is not absent from the unmiraculous; God is the location of the deepest meaning of the unmiraculous. God is the reality that makes most complete sense. Indeed, that is close to a definition of God. And this is also how we understand the miraculous.
I started with a straightforward affirmation that at the first Easter, Christ was raised. This is a miracle, and the reason I think it happened is largely because of the person it happened to: I think that person had already showed himself to be sufficiently remarkable that we are here witnessing something at once extraordinary, and yet making the most profound sense. That sense continues to the present day because it promotes a just society in which people are to be seen and treated as equally valuable, and equally called upon to contribute.
I will finish with that thought. Science is an important component of such a just and creative society, but it is not the be-all and end-all of our lives. It can show us some of the meaning of the world, but not our whole meaning.