Arguing by Design (A.C. Grayling, 2013)

NOTE: The following article is taken from The God Argument: The Case Against Religion and for Humanism, pp. 73-82.


Proponents of the teleological argument deduce the existence of a deity from the appearance of design in nature. Strictly speaking, the argument is only entitled to try proving the existence of a designer; it is a bigger step to say that this agency created the universe as well as designed it, because however natural it might be to think that an agency capable of designing a universe might also be capable of creating it, nevertheless there is no evidence in the appearance of design that the designer was the creator too.

But grant, for a moment, that if there were a designer, it would also be the creator; it is an even bigger step to get from there to the deity of a particular religious tradition, such as the Judaeo-Christian tradition. There are many other religions and mythologies in which the agency credited with creating the universe has no further interest in it, or at least no interest in humans.

Contemporary ‘Intelligent Design’ (ID) advocates are careful not to say what they take the teleological argument to prove the existence of, other than an Intelligent Designer – at least not while they are trying to get their textbooks into American schools alongside biology textbooks. Their creationist or ‘Creation Science’ predecessors were less careful, stating straight out that they took the argument to establish the existence of the Judaeo-Christian ‘God of the Bible’. As the foregoing consideration shows, ID advocates would have a task to advance beyond an Intelligent Designer if their eventual aim – as everyone knows it is – is to defend a traditional Judaeo-Christian commitment. (Islam is a creationist religion and faces the same problem.)

Many of those in the eighteenth century who today would call themselves atheists described themselves as ‘deists’ because they were unable to see how the universe and life could begin without a creative act of some kind.8 They were puzzled by the obvious difficulty that positing a creating agency merely pushes the problem back a step – where did the creating agency pop up from? what explains it? – yet in the absence of any other resource they accepted the fudge. Note that this is not the same thing as an argument from design, but rather is a version of the argument that says: ‘in the absence of having any clue as to what the explanation might be for something, just settle for saying “a god did it”.’ This is the ‘god of gaps’ move.

The deists also held, on the sound empirical evidence otherwise available to them, that the creating agency was no longer at work in the universe – that it was either no longer around or no longer interested. Consequently they did not subscribe to any religious practices other than for form’s sake. At that time it was, in social terms, very difficult not to pay lip-service to the forms.

As the deists’ dilemma shows, the teleological argument was taken seriously in the eighteenth century, by which time two centuries of science had proceeded far enough to reveal many of the natural world’s beautiful complexities, but not far enough to explain their origin and development.

William Paley by George Romney
William Paley by George Romney

The most famous statement of the argument from design was given by William Paley. In his Natural Theology (1802) he invites us to imagine finding a watch on the ground while out for a walk, and being forced to conclude from an examination of its structure and properties that it was made by an intelligent agent. But if we think this of a watch, which gives every indication of being wrought by a purposeful agent, how much more so must we think the same of the eye, which, he wrote, ‘would be alone sufficient to support the conclusion which we draw from it, as to the necessity of an intelligent Creator’.

If this is the most intuitive statement of the design argument, the clearest statement of its logical structure is given by David Hume in his posthumously published Dialogues Concerning Natural Religion (1779). He has his character Cleanthes say:

David Hume
David Hume

“Look round the world; contemplate the whole and every part of it: You will find it to be nothing but one great machine, subdivided into an infinite number of lesser machines, which again admit of subdivisions to a degree beyond what human senses and faculties can trace and explain. All these various machines, and even their most minute parts, are adjusted to each other with an accuracy which ravishes into admiration all men who have ever contemplated them. The curious adapting of means to ends, throughout all nature, resembles exactly, though it much exceeds, the productions of human contrivance; of human design, thought, wisdom, and intelligence. Since, therefore, the effects resemble each other, we are led to infer, by all the rules of analogy, that the causes also resemble; and that the Author of Nature is somewhat similar to the mind of man, though possessed of much larger faculties, proportioned to the grandeur of the work which he has executed. By this argument a posteriori, and by this argument alone, do we prove at once the existence of a Deity, and his similarity to human mind and intelligence.”

Hume rejected this argument. His rejection of it turns on three points: on the weak and misleading nature of the analogy between natural things and man-made machines; on the fact that there are alternative explanations of how natural phenomena came to be as they are; and – the point made above – that if the argument established that the universe must have been designed, the most this could establish is the existence of a designer.

In accepting this last point the deists were of course being persuaded by the supposed analogy in play. But they were also making use of the fundamental principle that everything has a cause. Philosophical thinking about causation was influenced by Aristotle’s doctrine of causation, which turns on a fourfold distinction between the ‘formal’, ‘material’, final’ and ‘efficient’ causes of things. The ‘formal cause’ is the plan or design of something. The ‘material cause’ is the stuff out of which it is made. The ‘final cause’ is the purpose or end for which it came into existence. And the ‘efficient cause’ is the actual work that brought it about. On the analogy proposed by the teleological argument, just as intelligence ineliminably figures in any account of the final and efficient causes of human artefacts, so a like intelligence must be supposed to explain the final and efficient causes of natural things.

Stained-glass window showing William of Ockham
Stained-glass window showing William of Ockham

The weakness of this analogy, however, is revealed by the second counter offered by Hume. This is that there are other and better explanations of natural phenomena. Although cosmology and biology had not reached the levels of explanatory power that experimental and theoretical advances have since together permitted, Hume could see that postulating a designer to explain the appearance of nature blunts Ockham’s Razor, the principle which states that one must employ the fewest assumptions and invoke the least number of entities necessary to explain something. So if there could be alternative explanations which are simpler in themselves and more consistent with observed fact, invoking an extra agency is unnecessary. If Ockham’s Razor were not a principle of enquiry, why not hypothesise that flowers are coaxed out of their seeds and up through the soil by fairies, one for each flower?

Moreover the design hypothesis is implausible because it purports to offer an explanation by invoking something itself unexplained. The deists who felt disquiet about this should have taken their disquiet seriously, because explaining something by something unexplained amounts, obviously, to no explanation at all.

And finally the argument is inconsistent with the many examples of bad design that nature offers us (wisdom teeth and the human appendix merely begin a very long list), together with nature’s failures (most life that has ever been on Earth is now extinct) and repeated efforts at producing structures (there are nearly two dozen different evolutionary pathways to types of eyes, something Paley did not know). The first point is a logical point, the second is an empirical one.

One way that defenders of the teleological argument seek to salvage it is by saying that the deity works indirectly, by making natural laws the instrument for realising his designs. He creates the laws, then the laws create nature, thus fulfilling his purposes. This however is an even worse violation of Ockham’s Razor; it accepts that natural laws create the universe by themselves, and then postulates an additional entity to be a creator of the laws.

This is also an example of what Karl Popper meant when he said that a theory which is consistent with everything – which says that nothing can refute it – explains nothing. Consider the ID proponent who rejects the theory of biological evolution while arguing that the designer works through natural laws. He moves the designer further back down the causal chain so that no example of naturally occurring adaptation is inconsistent with this hypothesis – which therefore makes the hypothesis empty.

A more contemporary form of teleological argument turns on the idea of ‘cosmic fine-tuning’. This argument begins from the observation that the universe’s initial conditions, and the physical laws and parameters operative within it, are ‘fine-tuned’ in such a way as to make it possible for life to appear on this planet. Had they been different in even the smallest way, life as we know it could not have happened.

For example: if the strong force in the atomic nucleus had varied in either direction by more than 5 per cent, or if the electromagnetic force binding electrons to atomic nuclei were stronger or weaker, life could not have emerged. If the relative masses of neutrons and protons were different, life could not have emerged. If the gravitational force were different even by a minute amount, main sequence stars like our own sun could not exist and accordingly life of our kind would be much less likely.

If the ‘big bang’ had not been exactly as it was, either the universe would have collapsed upon itself immediately, or it would have expanded too rapidly for the evolution of stars like our sun; so either there could have been no planet Earth with life on it, or at very least our kind of life would not have appeared.


The concurrence of these just-right values constitutes what has been called ‘the Goldilocks enigma’. How can the universe be so extraordinarily apt for life to emerge on our planet, given the infinitesimal chance that nature’s laws should all coincide in the right way for it? Therefore – some say – it must have been designed by a purposive agency.

Much might be said in response. We are asked to think that there is an agency whose aim was to produce us by bringing it about that, after nine billion years or so – the universe is about thirteen billion years old – forms of life would emerge that after a further four billion years would eventuate in us (the first prokaryotes appeared on our planet about that long ago).

Let us leave aside the fact that this speculation makes us the aim of the great universal story; all those billions of years, billions of galaxies, billions of stars – it is all aimed at producing us, with our wars, our dentistry needs, our fashion sense. Even if these things were part of the design to test us so that we can get into another universe – the posthumous one – it would seem a trifle excessive. The least one can say is that it is a view that does not suffer from immodesty about the importance of human beings to the cosmos.

Consider instead the following fact. If my great-great-great-great-great-grandparents (all 64 of them, living about two hundred years ago) had not lived where they did, and done the things they did – and pretty exactly as they did them – I would not exist. But this is a retrospective observation, which I can only make because in fact I exist, even if I am filled with wonder at the (very fortunate for me) millions of coincidences which resulted in me. If my forebears had been inconsiderate enough to do other things in other ways and places instead, with the result that I did not exist, I would not now be marvelling at how fine-tuned history was in bringing it about that I exist. I do not however think that my existence was the point and purpose of all these events, however lucky for me. Rather, I think that it is only because I exist that I see that I would not have existed unless these coincidences occurred.

The ‘Goldilocks dilemma’ of my personal existence, and that of the universe’s parameters and laws, is exactly the same thing.

A variant explanation of the illusion of purpose in the ‘fine-tuning’ version of the design argument is provided by Voltaire’s Dr Pangloss in Candide, a book prompted by the 100,000 deaths in the earthquake and tsunami which devastated Lisbon in 1755. The catastrophe made Voltaire doubt that this world is the ‘best of all possible worlds’, or that it is under the government of a benevolent agency.


Consider Dr Pangloss’ explanation of the human nose, which is that it was purposely designed to support spectacles. This exposes the fallacy in the fine-tuning argument, to see which one needs to know a little logical technicality, as follows.

The fact that a human nose (use the letter X to symbolise the nose) is a necessary condition for spectacles to be perched in front of the eyes (use the letter Y to symbolise ‘spectacles being perched in front of the eyes’) does not entail that, because Y is the case, X is in itself necessary. ‘Necessity’ in the logical sense of ‘having to be so’ is not the same thing as the necessity involved in a ‘necessary condition’ – here things have to be so only relative to something else’s being the way it is. In the case of X’s being a necessary condition relative to Y, but not in itself necessary, X could have been different, and if it were so, there would, or at least might, be no Y. For example: if humans did not have noses, spectacles might be worn as goggles are, held before the eyes by an elastic strap.

onion10-5This is just how it is with the universe. We humans are the Y of which nature’s parameters are the X. We exist because the parameters are as they are; had they been different, we would not be here to know it. The fact that we exist because of how things happen to be with the universe’s structure and properties entails nothing about design or purpose. Depending on your point of view, it is just a lucky or unlucky result of how things happen to be. The universe’s parameters are not tuned on purpose for us to exist. It is the other way round: we exist because the laws happen to be as they are.