Fit for Purpose? Darwin’s Excellent and Meaningless Theory

Sermon given at St Chad’s, Shrewsbury, on the occasion of the 2015 Darwin Festival. Reading: Genesis 8:4-13.

Abstract

Darwin’s Theory of Evolution by Natural Selection is often referred to as “Survival of the Fittest”, a phrase which plants a subtle yet dangerous notion of excellence in the casual listener. A better label might be “The Survival of the Fitting” as often, species fit in to their environment in very inconspicuous ways.

Science alone gives us no reason to think that our era is special, and every reason to think that the species which exist today are simply a snapshot of forms that life could feasibly take on earth, with many life-forms no “better” or “worse” in any objective sense.

The everyday work of scientists takes place under the assumption that no sense of “meaning” or “purpose” is required to understand the natural world. Yet humans naturally yearn for a sense of direction in life. Expecting Darwin’s theory to provide this leads us down dangerous paths; at best, biology indicates what humans could be, not what we should be.

As for whether the Bible is a suitable guide, we will deal briefly with whether it is trustworthy on questions of the creation of the universe, the existence of species, and the first sin of the human race before embracing it as our natural selection for the perfection of our species!

We’ve just heard a report of a scientific experiment read straight from the pages of the Bible. Noah is, in fact, the Bible’s first recorded research scientist!

We know Noah was a scientist because – we are told – he does three things characteristic of a research scientist.

First, he adjust the details of his experiment one step at a time. He tries sending out a raven – then a dove.

Second, he repeats his experiment. At least, he can’t repeat the raven experiment because it hasn’t come back, but he can repeat the dove. In trial 1, it returns quickly. In trial 2, it returns with an olive branch. In trial 3 it corroborates the raven experiment by failing to return. In this way, Noah knows the water is drying up.

Third, Noah uses a complicated experimental set-up to test what a non-scientist would have approached by a more crude method – for instance, looking through one of the ark’s portholes!

I’ve used this story before when preaching about science and religion, but it seems especially appropriate here in the church where Charles Darwin was baptised. Like Noah, Charles Darwin sailed on a voyage of discovery. Like Noah, birds played a crucial part in the way Darwin tried to understand the world around him. In Darwin’s case, observing the bird-life of the Galapagos islands, and many other kinds of species, led him to propose a theory of evolution by natural selection.

Darwin’s idea is often summarised as the “survival of the fittest”. That’s a very dangerous phrase! In the English language, “fittest” implies the best, the strongest, the pinnacle of creation! What Darwin was actually describing was the survival of the most fitting. Kinds of creatures which fit best into their environment are most likely to survive. One way of fitting in is to become the strongest or smartest, but that comes with a price – big brains and thick limbs require more food energy to maintain.

Another way of fitting in is to become small enough to hide away, or excellent at camouflage. This was even the subject of a recent Doctor Who episode, where the Doctor mused about what would happen if a species evolved to perfect the art of hiding – how would we even know if it existed? The term ‘evolution’ itself has also picked up a flavour of progressing from good to better to best… what comes to mind if you try to imagine something ‘highly evolved’?

The only direction which evolution actually respects is “nearby”. A genetic mutation cannot change a lot of things at once. An organism gives rise to descendants which are similar, but perhaps not quite the same. The descendants most fitting to the environment at the time will be the most successful at surviving and breeding. There is nothing to stop evolution from ‘backtracking’ and going back to a previously used design, just as you might drive the same route to work on Monday and Wednesday even though you took a different path on Tuesday.

When we human beings analyse the abilities of an organism, we might judge a particular species to excel at doing something – but only by being the ‘best’ on some scale we choose to use. And species which excel at one thing do so at the cost of other abilities. Without mechanical aids, we human beings cannot fly, swim underwater for 90 minutes, or keep ourselves warm in an Arctic environment. Eagles, whales and polar bears might well dispute our claim to be highly evolved. And author Douglas Adams pointed out how the dolphins smile because they know they are superior to mankind, having learned how to spend all their days mucking about in the water and having a good time! Human beings, meanwhile, are marked by what we would call design flaws, if we were deliberately designed: back pain, flat feet, varicose veins and piles!

The world around us, as we know it, represents one slice in time, no more privileged than any date in the future or in the past. Natural selection will continue to cause species to change and adapt. Some, no doubt, will achieve new records on some scales, simply because the stepwise progress of evolution put that ability “nearby” to some existing genetic plan for the first time. Others will re-trace well trodden paths. When it comes to the ability to reason and use language, Homo sapiens does indeed hold the record for Planet Earth. Does that mean we will automatically increase in those abilities? If it is biologically possible to do so without needing undue food consumption, than random mutation might allow this to happen – there again, as Dawkins colourfully put it, the watchmaker is blind, so nothing is guaranteed.

When it comes to us human beings, we can no longer speak of ‘natural selection’ alone. Because our medical skills and human compassion cause us to care for sick members of our own species, and indeed our pets and our livestock, we enable less-well-fitting creatures to survive and breed, preserving gene lines which would otherwise have died out. If anything, this has a cooling effect on the rate at which humans and our companion and farm animals evolve. There again, the ability to perform deliberate genetic modifications, which will inevitably be permitted to some degree despite the protestations of religious leaders from my own and other traditions, will change the human race in ways which will ripple through future generations without limit. This has always been true of random mutation, but now Homo sapiens is personally responsible for some of these lasting changes whose consequences cannot be fully predicted.

As human beings, we have a deep-rooted tendency to seek meaning and purpose in the world around us. The ancient philosophers, following Aristotle, spoke of four causes: formal, material, efficient and final. In other words, we can understand a thing if we can answer four questions: What is it? What rules does it follow? What started it in motion? What is its purpose? Modern science makes do with three causes. We choose a thing, identify the rules it follows, and if we set it going in a certain way we can predict how its future will unfold.

Science doesn’t generally ask “What’s the purpose of this?” or “What is the final cause?”. To a scientist, this only applies to objects manufactured with a purpose in mind. Human artefacts have a final cause. Richard Dawkins has written at length about how evolution by natural selection produces “designoid” objects, which look as if they had a final cause but whose characteristics can be totally explained by the unfolding of natural selection.

Nevertheless, we do seek meaning and purpose in the world around us. As a Christian believer, I acknowledge that God has a purpose for the human race as a whole – to enter into eternal life in union with Christ – and a particular vocation, or as John Henry Newman called it, ‘some definite purpose’ to which God calls us individually. I also recognise that because God’s plan was for rational creatures to come into being, it was necessary for the natural world to be of a form which allows us to live in it. I reserve judgement on whether God intervened by overriding the rules, by loading the dice or simply by setting up a favourable set of rules; but I am not the kind of Deist who believes God wound up the clockwork and retired, because I do believe in a God who works occasional miracles in answer to prayer. I simply wish to avoid invoking God to plug any gaps in our current scientific knowledge of how the universe and life came to be, because I know that my scientific colleagues have an excellent track record in working out how seemingly-unlikely things can in fact happen profusely in the right circumstances.

I began with the story of Noah, taken from those early chapters of Genesis which contain stories of deep meaning. Way back in the third century of the Christian Era, a pagan philosopher, Celsus, poked fun at Christians and Jews because of the first books of the Bible. He accused the believers of being “silly” because they accepted the first chapters of Genesis as literal and historical. The Christian writer, Origen, in turn called Celsus “silly” because both contemporary Christians and the writers of the age when the Scriptures were composed, knew that the whole point of these writings was the symbolic meaning, not the literal one! It was only in the light of the 16th Century Reformation that both Protestant and Catholic Christians started trying to read Genesis in a more literal way. Genesis declares that God created beings ‘according to their kinds’, but we need not read this as revelation that species are fixed and cannot evolve; it is simply the way the author describes animal and plant life as it existed at the time of writing.

The Epistle to the Hebrews acknowledges that God has spoken more clearly through Christ than previously. We must therefore take seriously the words of Jesus when he appeals to Adam and Eve as the basis for the permanence of marriage; even so, we can understand that Christ was affirming the moral point, not the historicity, of the Genesis account. We must also take seriously St Paul’s assertion that the whole human race sinned in Adam; however, the claim that we all descend from an original sinner is no more or less radical than asserting that we all descend from an original mutation responsible for one or other of our human traits.

My dear brothers and sisters in Christ, and skeptical guests here this evening, I put it to you that Darwin’s Theory – to give it its full title – On the Origin of Species by Means of Natural Selection, or the Preservation of Favoured Races in the Struggle for Life is a meaningless theory. The only illustration in Darwin's Origin of Species: a tree diagram showing branching evolutionBy that I do not mean it is poor science or badly-written English. I simply mean that it does what science does – it describes what is, and has no concept of what “should be”. It is an excellent starting point, much improved upon by our subsequent knowledge of genetics. Yet the very language we use fools us into speaking of ‘highly evolved’ creatures as if they were morally superior, or creatures with ‘defective genes’ as if they were morally lacking. Biology is amoral, but we have to keep reminding ourselves of this lest the natural use of language should seduce us. I note with interest that there is only one diagram in the Origin of Species, and it is a tree where all end points – existing species – have equal status. Why? They are equal in one crucial regard, they are alive now.

The fact that human beings have evolved to our current abilities tells us nothing about whether we will, or whether we should, continue in that direction of travel. Many science fiction authors have speculated about humans evolving to become non-corporeal creatures; my co-religionist Teilhard de Chardin speculated that creation was called to reach an ‘Omega Point’ of maximum complexity and consciousness in union with God. It would be a mistake to say that Darwinian evolution requires or even suggests these possibilities; this would be to apply a scientific hypothesis beyond the limits of its applicability.

If we wish to know what kind of eternal existence God is calling us to, or how we should live our lives on earth, we can turn to the Bible and find secure answers in the teaching of Jesus. Only the Heavenly Man can teach us the values of Heaven and how we should journey there. As for the things of earth, the story of Noah gives us reason to trust that the status of the world around us can be discerned from ravens and doves – so why not the finches and mockingbirds of the Galapagos?