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Bible Interpretation Why Believe in God?

Design Argument

One of the most common reasons why people say they believe in God is that the universe seems to have been intentionally designed.

In ancient and medieval times hardly anyone doubted this. They disagreed about which gods had created the world, how, and for what purpose, but nearly everyone thought it was designed, and designed for a purpose. Arguments defending design only appear when other people deny it, from the seventeenth century onwards.

I describe three stages. The first focuses on the order of the world expressed through the laws of physics. The second focuses on biology, and the way every species is well adapted to its environment. The third goes back to physics and argues from the fine tuning of physical laws.

I shall not include the new American movement which calls itself ‘intelligent design’. The purpose of that argument is to deny evolution, and despite its name I think it’s best to think of it as an interventionist argument rather than a design argument.

Order

First then the argument from order. The point is that the regularities of nature apply universally. The medieval theologian Thomas Aquinas offered ‘five ways’ of reasoning that God exists. The fifth is that ‘an orderedness of actions to an end is observed in all bodies observing natural laws’.

This argument works as an analogy: when we observe that something is ordered, we assume an intending mind has ordered it, so when we observe that the physical laws of the universe are ordered we infer that it too must have been designed by a mind.

By the time of Isaac Newton 400 years later the mechanistic paradigm was well established; the universe was conceived as a giant machine, like a clock wound up at the beginning and ticking away thereafter according to the laws of physics. Newton thought the motions of the heavenly bodies suggest a designer with a knowledge of mechanics: ‘This most beautiful system of the sun, planets, and comets, could only proceed from the counsel and dominion of an intelligent and powerful being’.

Criticisms of order argument

The most influential critic of the design argument was David Hume, writing in the middle of the eighteenth century. Hume was an original thinker, in many ways far ahead of his age, still greatly admired today. He posed radical challenges to the ideas of his day and was quite honest when he didn’t know the answers. One of his questions was how we can know that our five senses perceive the world as it really is: indeed, how can we know there is a world outside our minds at all? The inherited answer was that a good God would not deceive; but Hume pointed out that we have no proofs that there is a God at all, let alone a God who would not deceive. How then can we know that there really is a world outside our minds? Here’s his answer:

I dine, I play a game of back-gammon, I converse, and am merry with my friends; and when after three or four hours’ amusement, I wou’d return to these speculations, they appear so cold, and strain’d and ridiculous, that I cannot find in my heart to enter into them farther’.

In other words he doesn’t have an answer so he distracts himself.

He had three main arguments against the design argument. Firstly he argued that order is not proof of design. We see order in many situations but only in a minority do we know it is caused by an agent. This point applies to all versions of the design argument, and we’ll come back to it.

Secondly we consider one thing the cause of another when we have observed that the effect follows the cause with regularity. If we could observe lots of universes, and notice that the ones governed by order are designed by God, then we could infer that this one, being ordered, is probably also designed by God; but we can’t. This universe is the only one we know about, so we cannot appeal to any regularities.

On this point Hume seems to be making an error which is still very common today. The error is to assume that science always works by induction from repeated observations. This is how Francis Bacon said science ought to work, but in fact scientists often do develop theories about unique events. The most obvious ones are the Big Bang and the origins of the human race. Nevertheless Hume is right to conclude that order does not prove design.

His third argument is that when we deduce a cause from an effect, all we know about the cause is what the effect indicates. If the universe has indeed been created by God, this shows that God possesses the amount of power, intelligence and benevolence revealed in the universe but no more. He criticized theologians for assuming that they knew more about God than the design argument could establish; perhaps the universe was made by a committee of designers, or was a poor experiment in universe-making by an inferior god, or was created by a god who has lost interest in it and allows it to continue regardless of its condition until it breaks up with age.

I find this argument interesting because it reveals the extent to which Hume and his contemporaries had, by the middle of the eighteenth century, lost touch with traditional forms of religious speculation. For thousands of years religious believers had debated theories like these. By Hume’s time these creative speculations about the nature of reality had become inaccessible, because most Catholics and Protestants had reinterpreted their inherited doctrines as unchanging divine revelation, to be accepted without question. Once they had done this reinterpreting, they could no longer treat their doctrines as attempts to explain the nature of reality.

The converse was Descartes’ dualism. Writing a century before Hume, Descartes had described reality as two spheres, one physical and one spiritual. The spiritual sphere is where God, human souls, values and purposes reside. The physical sphere consists only of atoms pushing each other according to laws of nature, and they only have instrumental value. What happened between Descartes’ age and Hume’s age was that all the interesting developments took place in the physical realm, where science discovered more and more. From that perspective the only relevance God could possibly have was to be its original creator. As the spiritual realm gradually became an optional extra the original creation of the world became the only reason for believing God exists. It was at this point, and only then, that Hume’s argument became convincing. The medievals would never have found it convincing because they had never separated all value, meaning and morality from the physical world, so they had other reasons to believe in God, in addition to design.

Hume was right to observe that the inference to a designer does not amount to proof. Others were arguing that it did. Since then there has been a major change of expectations. Then, the argument was about whether the order in the world proved the existence of a designer with absolute certainty. This was typical of Enlightenment thinking: they often expected reason to produce absolute certainty. Today we accept that absolute certainty isn’t available: what we’re looking for is the best available hypothesis. So defenders of the design argument today claim that the best explanation we’ve got of the world’s order is design by an intelligent being. We don’t expect to prove it; after all, I can’t prove that you exist. We just think an intelligent divine being is the best available explanation. Opponents argue that the laws of nature just happen to be there.

Adaptation

The argument from biological adaptation appeals to the suitability of organs, organisms or species for their biological role. It was most popular from the seventeenth to the nineteenth centuries.

Science was advancing rapidly, particularly in England, and in England it was often led by Church of England clergy. They believed the purpose of the world, and of human life, was to be found in the intentions of God.

The first major work in this tradition is John Ray’s The Wisdom of God Manifested in the Works of Creation, 1691. Writing before the idea of evolution had become popular, he believed that the earth and all its plants and animals had been created in their present form in the beginning, but he allowed for change through natural forces and human cultivation of the land.

William Derham’s Physico-Theology (1713) applied the design argument to new subjects, including human population theory and interrelationships in nature which do not affect humans. Derham was the first to express ideas which later became central to ecology. He introduced both specific processes like the food chain and the overall picture of the self-evident wisdom of the Creator, the value of all things, and their interrelation in a coherent whole.

These theologians stressed that human life has a purpose. In practice, that purpose was identified with the exciting changes being made possible by the new sciences. Those who did not believe in the design argument were also enthusiastic about the new future being opened up; but the design argument could give it a seal of approval as God’s plan for humanity.

What kept the design argument popular was the countless new examples from the natural sciences. As the world was being studied in increasing detail, there was a sense of excitement about its wonders. Deists argued that the revelation of God through nature meant the revelation through Scripture was no longer needed, especially as nature was easier to understand.

Paley

The last great work in this tradition was William Paley’s best selling Natural Theology (1802). Paley was the Archdeacon of Carlisle, one of the many clergy with a keen interest in the natural sciences. He was not an original thinker, but his book popularized the ideas of the natural theologians and for a hundred years it was the standard work of natural theology. When the evolution debate broke out, it was his work which provided the background against which evolutionists reacted.

Paley wrote his book about 50 years after Hume and 50 years before Darwin. Many commentators today think he was behind the times, using arguments which Hume had already refuted, and which Darwin would well and truly bury. I don’t think this is fair to him.

Paley took for granted the science of his day. He accepted that the world was only a few thousand years old and all the species alive in his day had been there from the beginning. Nevertheless the idea of evolution was around; both Hume and Paley knew of it, though in their day there was very little scientific research to justify it.

Most of Paley’s work, like that of earlier natural theologians, piles up illustrations from the sciences to illustrate divine design. The key arguments are expressed in his watch analogy:

In crossing a heath, suppose I pitched my foot against a stone, and were asked how the stone came to be there, I might possibly answer, that, for any thing I knew to the contrary, it had lain there for ever; nor would it perhaps be very easy to show the absurdity of this answer. But suppose I had found a watch upon the ground, and it should be enquired how the watch happened to be in that place, I should hardly think of the answer which I had before given, that, for any thing I knew,the watch might have always been there. Yet why should not this answer serve for the watch, as well as for the stone?... [Because] its several parts are framed and put together for a purpose, e.g. that they are so formed and adjusted as to produce motion.

There follows a description of the parts, followed by:

The inference, we think, is inevitable; that the watch must have had a maker; that there must have existed, at some time and at some place or other, an artificer or artificers who formed it for the purpose which we find it actually to answer; who comprehended its construction, and designed its use.

Aware of the usual objections to the analogy, he then argues that our inference to a watchmaker would not be invalidated in any of the following cases.

(i) If we had never seen a watch made or known anybody capable of making one, or if we were unable to make one ourselves or understand how it was made.

(ii) If the watch sometimes went wrong.

(iii) If there were some parts of the watch whose use we could not understand, or which seemed to us to be entirely superfluous.

(iv) If somebody pointed out that the particular combination of the particular metals was just one out of many possibilities; and if it had not been there, something else would have been there with another unusual combination of materials. I’ll come back to this. Paley’s point is simply that arguments of this type would not convince us that the watch had no designer.

(v) If it were argued that the watch were nothing but the result of the laws of metallic nature. This takes us back to an issue about the laws of nature which I described earlier: are they forces, or are they descriptions of regularities? All we ever observe is the regularities. Paley is right to argue that laws of nature cannot make a watch, because they are only observed regularities.

(vi) If it were argued that the observer did not know about the matter. Finding the watch, as described, would be enough information to infer a watchmaker.

(vii) Paley next proceeds to a discussion of indirect creation. Scientific discoveries had characteristically elaborated laws by which one event was caused by another, or one plant or animal created by its parents. Atheistic mechanists were arguing that the creation of everything could be accounted for in this way, without invoking a divine cause. Paley replied that indirect causation does not in any way dispense with the need for an intelligent designer, and, if anything, increases the evidence for intelligent design. If the discoverer of the watch found that, as well as being able to tell the time, it contained within it a mechanism which could create new watches like itself, this would increase our admiration of the machine rather than reduce it. After Darwin published his Origin of Species, Frederick Temple, Archbishop of Canterbury, extended Paley’s point to refer specifically to evolution: if the watch proved able to create better watches than itself, that too would be evidence of design.

We can all agree with Paley this far: if what we see in the watch implies design by an intelligent being, then we infer an intelligent designer. Furthermore, how the designer set about manufacturing it - whether directly or by means of a watch-making watch - is irrelevant to the main point. But it is precisely design by an intelligent being which atheists today do not perceive.

Paley knew nothing of twenty-first century atheism. The atheism of his day was different. The eighteenth century had been gripped by excitement about the new sciences, and their power to uncover the mysteries of the universe. That the world was full of the most astonishing intricacy and breathtaking detail was not under dispute. If anybody denied the wonder of it all, it was conservative theologians with their warnings about the Fall and the wrath of God. Atheists agreed with Paley that the world was wonderfully intricate and seemed to be astonishingly well designed. Against that kind of atheism, it made good sense for Paley to insist that design implies a designer. During the nineteenth century, however, atheism changed – perhaps partly in response to Paley’s arguments, though there were other reasons. Later atheists denied that they perceived any evidence of design in the world. To be consistent about their atheism, they suppressed their sense of wonder and learned to evaluate whatever scientists discovered as ‘nothing but’ a development from, or adaptation of, something else. On this newer basis, Paley’s analogy no longer holds.

Darwin

Charles Darwin’s Origin of Species was published in 1859. It made evolution more credible by a substantial amount of research data, and by proposing a means, namely natural selection.

There are two main implications for the design argument. The first is that it offers a God-free account of the process by which living beings developed into the rich array we have. In some of his writing Darwin wrote that his account refutes the design argument: ‘We can no longer argue that, for instance, the beautiful hinge of a bivalve shell must have been made by an intelligent being.’

On this point I think Paley was right and Darwin was wrong. The theory of evolution describes the process by which the bivalve shell developed into what it is, quite independently of whether it was designed by God. We can conceive of three different positions: either it was a naturalistic process without any involvement by God, as atheists believe, or God set up the evolutionary process so that it would produce the bivalve shell with its hinge, or God set up the evolutionary process and left it free to produce whatever it would. Neither Darwin’s data nor the theory of natural selection offer any way to choose between these three.

What Darwin did achieve was to describe a process which would make sense even if God did not exist. In other words the appearance of design can have alternative explanations. Richard Dawkins suggests that Darwin made it possible for the first time to be ‘an intellectually fulfilled atheist’.

The other main implication was that whereas the natural theologians had emphasised the goodness of nature, Darwin’s idea of natural selection drew attention to the large amount of waste and suffering. Darwin was heavily influenced by Malthus, and stressed how organic life is a constant struggle for existence: ‘I cannot persuade myself that a beneficent and omnipotent God would have designedly created the Ichneumonidae with the express intention of their feeding within the live bodies of Caterpillars, or that a cat should play with mice’.

Paley had already covered this point. It seems to me that the difference between the two is that they both see the same things, and Paley infers benevolent design but Darwin does not. This is the situation today. We see the same processes in nature, but some of us are impressed by the glory and wonder and purposeful design of it all, while others are not so impressed at all.

Fine tuning

The fine tuning argument has developed over the last century. It is closely associated with the anthropic principle. The anthropic principle is about the conditions necessary for humans to exist. In its weaker form it simply states that what we can expect to observe in the universe must be restricted by the conditions necessary for our presence as observers. Nobody disagrees with this. The stronger form claims that the universe was, from the start, bound to be such as to produce us. This is more controversial.

I’m going to focus on the fine tuning argument without specific reference to humans. The point here is that the laws of nature are exactly what they need to be for life to be possible. The main variables which have to be exactly right are: the distribution of gas in the universe, the initial heat of the big bang, the weight of neutrinos, the total mass of the universe, the force of gravity, the force of electro-magnetism, the strong nuclear force, weak interaction, and the temperature of the interiors of hot stars. The slightest deviation in any of these values, a millionth either way, and life would have been impossible. They were all established within the first fraction of a second after the Big Bang.

This fine tuning has led many scientists to conclude that a divine power must have been at work. It is so overwhelmingly improbable that all these values should have become by chance precisely what is required for life to evolve. William Lane Craig puts it: ‘The point is that it is unimaginably more probable that the universe should be life-prohibiting than life-permitting, and that the best explanation of the cosmos as it is may well be intelligent design.’

Here the analogy would be not with a watchmaker but with a listener tuning a radio or a mechanic tuning a car engine, to get a meaningful result. However, is the argument valid?

If we assume an enormous range of possible initial states of the universe, all equally likely, then any one of them is extremely unlikely to happen. But we don’t know that they were all equally likely, and even if they were, it looks as though any one of the alternatives would have been equally improbable.

Michael Polanyi, writing in 1957, offers an illustration which unfortunately can no longer be seen. In north-east Wales is a town called Abergele. At the time he was writing its railway station had a lawn into which small white pebbles had been set, spelling out the words ‘Welcome to Wales by British Railways’. If we were to calculate the probability of those pebbles just happening by chance to be in that arrangement, it is so small that we would naturally assume they had been arranged like that deliberately. Polanyi compares this with an alternative situation. Suppose somebody were to pick up the pebbles and scatter them at random over the lawn, so that they did not spell out anything meaningful, and we calculated the probability of this new arrangement happening by chance. The precise configuration of the new pattern would turn out to be equally improbable. The reason why we would impute human intention in one case but not the other is that we see order and meaning in it.1

Let’s apply the logic of this to the laws of physics. The only Big Bang we know about produced laws of physics which made our lives possible. It could have produced billions of different combinations of laws which did not result in life being possible, and we think that if any of those had happened they would have been equally disappointing: what we’ve got is the only one with a life-producing result, and we’re pleased. But is that just human bias? Humans find life valuable. Is that just our perspective, like a fish finding water valuable, or is it a real truth about reality?

Many universes

One way to lessen the odds is to assume there are lots of universes. Martin Rees argues that the life-permitting character of the actual world becomes less surprising if our universe is one of many.

Stephen Davis replies that there is no evidence that there are other universes. If there are, the life-permitting character of this universe still needs explaining.

D H Mellor rejects the probability arguments on both sides. Mellor claims that what is the case in other universes, if they exist, is irrelevant to the probability of the laws of our universe. Whether any one event is probable or not depends on what the laws of nature are, so if we are talking about the chances of the laws of nature themselves existing, it is meaningless to talk about any particular probability.

Some commentators have questioned the role of complexity. Usually when we look for explanations Ockham’s razor is a useful guide; when in doubt, go for the simplest explanation and don’t posit the existence of anything you don’t need to posit. So, in the absence of any divine mind directing the process, would a simpler universe be more probable than a more complex one? Or do we just assume that simpler things are more probable because our brains find them easier to understand?

Suppose we accept that it was extremely improbable for the laws of nature to be what they are, so this needs to be explained. It looks as if we may have to choose between believing either that there are billions of universes or that this universe has been designed by an intelligent God. Ockham’s razor would seem to suggest that God is the simpler explanation. But Richard Dawkins argues that it isn’t. He thinks invoking a divine being to explain complex phenomena, far from solving the problem, makes it harder because God, as their creator, would have to be even more complex, and we would then have to explain how God came to exist.

And, of course, Ockham’s razor doesn’t always produce the right answer anyway.

Summary

To summarise. All versions of the design argument appeal to some aspect of the universe which seems most easily explained as design. Some kind of god must have designed the universe to be like this. However there is no certainty about it. It is also possible to argue that there was no design, and that the universe only appears designed because we are used to attributing certain kinds of processes to intentional design.

A pattern is developing. This is the same result as we got from the cosmological argument and the argument from religious experience. In each case, the most natural explanation of what we find is that there is a God at work, but other explanations are possible.

This theme will appear again in the last two sessions, in June and July, when we look at value, purpose and morality. In April and May we’ll look at the presuppositions we all make, in order to believe that we know anything at all: that the world is ordered, and that the human mind can understand that order. Can we justify these presuppositions, and do we need to believe in God in order to do so?

Notes

1 Polanyi, Michael, Personal Knowledge, RKP 1958, pp. 33-35. In an earlier version of this web page I attributed this story to C D Broad. On checking my sources I found it came from Polanyi, not Broad.