Science and Religion

(Based on a talk given to Ilford County School on 19 March 2003)

One day in January 1348 a ship docked in Genoa in Italy, arriving from the Middle East. It brought with it the Black Death – bubonic plague, a disease now well controlled by modern medicine but then, like almost all illness, without cure. It took hold rapidly and spread out in concentric waves over the next 3-4 years across the whole of Europe.

Up to 1 in 3 of the whole population of Europe died.

Not only could they not cure it: people then had no notion of infection, or of germs or of their spread by rats. They came up with many possible explanations, like putting it down to the influence of the planets drawing foul exhalations from the earth. Almost everyone saw it as a punishment decreed by God, because the 14th century – like all ages in the eyes of religious commentators – was, after all, a uniquely wicked and dissolute age. The poet William Langland said in Piers Plowman: “These pestilences were for pure sin.”

The best people could do for cures was to fill the house with sweet-smelling flowers and spices, or prescribe medicine concocted from treacle, wine and chopped-up snakes.

It was a plague like AIDS today in Africa – beyond control – but worse: it killed people within a few days, and it was beyond all understanding.

The reaction of some of the most devout was to punish themselves so that God might abate his punishment of the whole people. They went round in groups beating themselves with whips studded with spikes and chanting hymns:

Ply well the scourge for Jesus’ sake
And God through Christ your sins shall take . . .
Had it not been for our contrition
All Christendom had met perdition. (1)

Ingmar Bergman portrayed just such a group of flagellants in his powerful film The Seventh Seal.

Why did they think the Black Death was a divine punishment? Why not just see it as bad luck? Simply because their whole understanding of the universe did not allow it. The Black Death reveals the mindset of people in a pre-scientific age.

Their universe was a fixed one, designed in every part by God, each part having its own decreed role, any step outside which would tend to upset the whole.

The Greeks more than 1,500 years earlier had begun developing a scientific way of enquiring about the world, and had (for example) realised the earth was round. Eratosthenes of Alexandria in about 200 BCE actually measured its circumference to within 1%, and Hipparchus of Rhodes a few years later measured the length of the year to within 5 minutes. But all this was forgotten in the centuries of Christian domination after the conversion of the Roman empire.

So what was the picture of the world held by these people, our ancestors about 650 years ago?

It would seem to us a poetic, inexact one. But not to them, because they had no other type of language or thinking to use. It was a static, sacred world., where the church had adopted some Greek theories about the world, especially from the philosopher/scientist Aristotle – but only in the form of fossilised lists and classifications – pickled, preserved in aspic, not as science but as a creed.

Thus, the world was made of four elements – earth, air, fire and water. Flesh was made of four humours – blood, phlegm, black bile and yellow bile – and sickness resulted from an imbalance of the humours. (Hence the resort by doctors to bloodletting, to reduce the presumed over-dominance of the blood – which amazingly persisted into the 20th century. (2)

In Shakespeare’s Pericles (3), Pericles asks “But hark! What music?” and answers himself: “The music of the spheres! Most heavenly music!” Here is another clue to the mediaeval view of the world – and remember, this was not mediaeval at the time: it was life being lived in the 14th century present.

What were the spheres? (4) They were concentric spheres, made of glass or crystal, revolving round the earth. In them were set, like jewels in a brooch, the moon, the sun, the stars and all the other heavenly bodies. What seems to us a theory (however alien) of a physical universe merged in an unnoticed way with their theology, for the angels and archangels and finally God himself resided in a strict hierarchy beyond the ninth sphere. Somewhere up there too you could find the blessed dead – or maybe you would do so after the Day of Judgement, when very soon (and it must be soon, given the dire portents of the Black Death) the dead would be raised – with their bodies – from the grave to face that final awful pass-or-fail examination.

Similarly, on earth, Man was the crown of creation, with Woman in second place. But there was an elaborate hierarchy among mankind, with the Pope as God’s vicar (which means “stand-in” or representative) on earth standing at the top of two pyramids. One was the hierarchy of cardinals, archbishops, bishops and priests, the other the secular structure of kings and princes. Kings ruled by divine right, so that disobedience of them was sinful. Kings of England by virtue of this divine right were believed able by their touch to cure the King’s Evil, the name they gave to a disease we know as scrofula. (The Church of England still has a service for this ceremony in some versions of its prayer book.)

Under the kings came an ordained social order through the nobles and the merchants till you got to the yeomen, freemen and serfs. The rest of creation – birds and animals and crawling things – were in a lower hierarchy, and then below the earth you got to the dread nether regions of purgatory and hell in another hierarchy of descending circles populated by the souls of the damned until at the bottom of the pit you found the devil.

And who was he? A rebellious angel, unwilling to give complete obedience to God. And what was his name? Lucifer – which means Bringer of Light – the light, without doubt of Knowledge. It is the same theme as in the Garden of Eden: knowledge is forbidden, and Eve made the sinful choice in choosing knowledge, for which God punished not just her but everyone ever since, according to the hateful doctrine of original sin. Similarly, too, in early Greek mythology: Prometheus (which means Far-Seeing) gave mankind fire and taught him how to use it and for this he was eternally punished by Zeus, the head Greek god: he was chained to a remote rock where vultures came every day and pecked at his liver.

In mediaeval times it was sinful not only to question this set order of nature, by which the power of the pope and kings was guaranteed, but even to pursue knowledge for its own sake. St Augustine had deplored the quest for knowledge back in the 5th century:

Another more dangerous form of temptation . . . is a certain vain desire and curiosity of making experiments cloaked under the name of learning and knowledge through a mere itch to experiment and find out. Thus men proceed to investigate the phenomena of nature though the knowledge is of no value to them, for they wish to know simply for the sake of knowing. (5)

The only enquiries you were meant to pursue were such vital matters of theology as how many angels could dance on the head of a pin – or, as St Thomas Aquinas seriously discussed in the 13th century, the problem that would arise at the Day of Judgement when the dead were resurrected from the grave with their bodies: what on earth would happen with cannibals whose bodies were made up entirely of the bodies of other people, which those others would reclaim, leaving the cannibals with no bodies of their own? (6)

It was even forbidden to translate the Bible into English. When William Tyndale began to do so – into beautiful English that was left largely unchanged 70 years later in the Authorised Version – he was tracked down before he could complete his translation by the agents of the revered St Thomas More and burnt at the stake.

Why were the church and the state (the two were only just coming apart) so much against knowledge? Because knowledge was power. If ordinary people could read the Bible, they could quote it back at the priests and argue with them. They might start questioning the entire social order – and that would be a rebellion not just against the local lord or the more distant king but against the church and even God, because the whole structure was divinely ordained and maintained.

So when the learning of the Greeks, which had been preserved and (especially as far as mathematics was concerned) extended by the Arabs during the European Dark Ages, began to filter back into Europe, real trouble was in store. For example, the idea was revived that maybe the earth was round. It was not just silly – anyone could see the earth was flat! – but more than that: it was dangerous. If the earth went round the sun, the earth was not at the centre of the universe. What happened to the idea of the spheres, of God above them all? The whole model, on which everything depended – the authority of the church, orthodox religious belief, morality – would collapse.

The church did its best to prevent such revolutionary thinking. The Inquisition, a department of the church, clamped down heavily, banning some books and burning others. Scientists like Galileo were imprisoned and forced to recant, or like Bruno were burned at the stake.

But slowly, despite all their efforts, the new thinking took hold. The Renaissance – which means re-birth – revived classical learning. The new attitude was later called Humanism – Renaissance Humanism – not in the modern sense of humanism as a non-religious ethical way of life but in the simple sense of giving value to a human perspective, not subordinating all thinking to the domination of God. It led to a great flowering of art and music, with the churches full of splendid art dedicated to the glory of God.

Soon, however, some people took advantage of the new freedom to put on different chains – the Protestant tradition arose which put all its emphasis on the individual and his soul and rejected the vainglorious outward display of the church. Where they gained power they took the second commandment literally and broke the statues and smashed up the stained glass in the churches and scratched out the religious paintings on the walls. If you think what the Taliban did in Afghanistan was bad, destroying Buddhist relics in the museum in Kabul and blowing up those monumental statues of Buddha, then what Henry VIII and Edward VI did in the churches and monasteries of England was many times worse.

So we got two Christian traditions in Europe – the Catholic one of baroque theology, richly decorated churches and elaborate and vital ritual, and the Protestant one which at its Puritan extreme is characterised by self-denial, bare, whitewashed chapels and personal conscience and salvation. (The American humourist H L Mencken said with some perception that Puritanism is “the haunting fear that someone, somewhere might be happy”.) And the two fought it out over the next few centuries of religious wars, inquisition, torture and burnings at the stake. Yet this horror and cruelty was carried out with good consciences by people for (as they saw it) the best of motives. It has been truly said that there is nothing so dangerous as a good man possessed by a bad idea.

About 300 years ago something new began. It was not a religious movement at all – though to start with almost everyone involved retained a belief in God. It was called the Enlightenment, and thinkers in Britain – especially (and in successive generations) Thomas Hobbes, John Locke and David Hume – were prominent in getting it started.

It was the beginning of modern thought. At its most radical it took nothing for granted and put no bounds on the questions that could be asked. For the first time, it saw tolerance as a virtue. It created the concept of the “rights of man” – Thomas Paine wrote a book of that title and strongly influenced both the American revolution (1776) and a few years the French revolution (1789) with its motto of Liberté, Egalité, Fraternité.

Under the Enlightenment, the word “science”, which had previously just meant “knowledge”, took on its modern meaning. Queen Anne was the last English monarch to touch sufferers from scrofula to cure them of the King’s Evil. Soon it was no longer blasphemous to dissect corpses to find out how the body worked. When there was an epidemic, you did not get on your knees or go in for self-flagellation: you looked for its causes and tried to eliminate them – so when in 1854 Dr John Snow worked out that an outbreak of cholera in London was linked to a particular water pump that was producing infected water, he removed the pump handle and stopped it spreading.

What has happened between 1700 and the present day is that our thinking has been set free. Just as so long ago with the Greeks, so now free enquiry has become valued and rational argument and experimental investigation have been used to find answers to all manner of questions.

This has not always gone smoothly: there has always been resistance from some parts of the church and the more reactionary parts of the establishment. Scientific advances have constantly been denounced and dire consequences have been predicted from “interfering with nature”. Churchmen fought against lightning rods, which interfered with God’s plans for his thunderbolts. They railed against inoculation and vaccination for the same reason: if God’s plan was for people to die of smallpox, men had no right to interfere. They denounced the use of anaesthetics – God wanted his creatures to feel the pain of surgery. John Wesley, the founder of Methodism, persisted in regarding epilepsy as possession by devils. (7) Even today some churches are trying to block stem cell research aimed at cures for inherited diseases and opposing various procedures in fertility treatment. Likewise, the Roman Catholic church in alliance with some Islamic governments is actively and effectively frustrating family planning work – and even the use of condoms to protect against AIDS – in the third world.

When serious investigation of the fossils of the dinosaurs dug up by the young Mary Anning in Lyme Regis began in the 1820s, the idea that the earth was more than a few thousand years old was still seen as outrageous: churchmen had calculated that creation could be dated to the year 4004 BC. Even worse if one creature had evolved into another, for the Bible said that God had created each of them and named them one by one. But the tide of enquiry was unstoppable, and eventually it lapped even at humankind itself, despite the best efforts of religious scientists such as Charles Lyell to maintain a gulf between animals and Man. (8)

Charles Darwin left man out of his Origin of Species (1859) but the message was clear long before he corrected the omission with The Descent of Man (1871). It was not just that science was undermining religion – the political and social order too were affected. If the natural order was the result of the survival of those best adapted to their environment, it was not laid down by authority. So questions were asked about the social order too. People might sing in church:

The rich man in his castle,
The poor man at his gate
God made them high and lowly
And ordered their estate.

but what if it was not God who ordered their estate but the workings out of a power struggle? The working class saw that they might become “the fittest” and became the strongest supporters of Darwin’s theory, flocking excitedly to lectures by Thomas Henry Huxley and others.

As scientists provided satisfactory explanations for more and more aspects of our experience, religion retreated further and further. From being the underpinning and explanation of everything, God became the “God of the Gaps”, surviving only in the areas that science had not yet colonised. Isaac Newton’s laws of motion and mechanics seemed to explain everything from the motion of the planets to the fall of an apple and threatened even to undermine the idea of free will.

The 20th century scientific revolutions created even greater difficulties for the orthodox believer. The universe had already broken out of its crystalline spheres, but now it has become vast beyond comprehension. How could God have created all that just as a setting for mankind? And it has become unbelievably old – creation took not seven days but 15 thousand million years before mankind emerged. Yet scientists have plausible theories for how it evolved from the first split second.

And now not even time can be counted on – it and space turn out to be aspects of the same thing, and time goes faster or slower depending on how quickly you move through space.

Even worse than relativity is quantum physics and the impossibility of making predictions about the behaviour of matter at the subatomic level. Yet the theory works and is basis of electronics.

Further still, the unravelling of DNA and the mechanism of genetics that eluded Darwin mean that much of animal and human behaviour could be explained at least in part by a study of the genes. It has gone so far that even the area of the brain most frequently associated with religious experience has been identified, and it has been found that people suffering from epilepsy are particularly likely to have religious experiences.

At first, painful as it was, the advance of science could be tolerated, but eventually it became intolerable. How did believers react?

Large numbers of them stopped believing. Even more relegated their belief to churchgoing and stopped trying to reconcile their everyday understanding of the world and their Sunday pieties. Instead, believers put more and more emphasis on the moral teaching of religion and saw religion more as a code of conduct than as a set of beliefs. What they often did not realise was that the code of conduct they adopted owed at least as much to secular, non-Christian traditions and Enlightenment thinking as to anything specifically Christian.

With the gaps for God getting far too small for comfort, two new and opposite ways of reacting have emerged.

One is to reject scientific explanations altogether. This is fairly easy for those whose education has given them only a limited understanding of science, but you find it also among some well educated people, even some scientists. Religious beliefs can be very powerful, and it is all too easy for people to hold inconsistent beliefs. As with the Queen of Hearts in Alice in Wonderland:

“One can’t believe impossible things,” said Alice.

“I daresay you haven’t had much practice,” responded the Queen. “When I was your age, I always did it for half-an-hour a day. Why, sometimes I’ve believed as many as six impossible things before breakfast!”

so some believers follow Tertullian, one of the early fathers of the Church (c160-c230), who notoriously said of Christianity “it is certain because it is impossible”.

So you get people today who still believe that the earth is only a few thousand years old. The clever ones do all sorts of bad science to try to get out of their difficulty, but it is blatantly bad science, and noone should be taken in by it.

The other way that believers have reacted is to adopt for everyday purposes all that science tells them, but then to try to add religion on as an extra. This either means retreating into poetic language, which is fine as long as it is not meant to be taken literally, or else they claim to find God in the underlying orderliness of the universe.

If you challenge them, they deny that this means that their God, as it were, wound up the universe by setting the rules and left it to run like a clock, because such a god would be completely remote and impersonal, but they are unable to deliver an account of the nature of such a god or say how they can communicate with him. It is difficult to make much sense of what such people say.

For example, Sir John Polkinghorne, an eminent scientist-cum-theologian, talks (9) of everything having “an origin in the mind of the creator who is the ground both of our mental experience and of the existence of the physical world of which we are inhabitants.” That sounds good, but what does it mean? He says that his god acts within the open grain of nature (10) because the grain of nature is already as aspect of god’s nature and he cannot act against himself – which seems very close to the clockwork model.

And people who believe in a god so remote have just as much of a problem with the existence of evil as any other believers. (11) Challenged about the Lisbon earthquake on All Saints Day, 1 November 1755, which killed 50,000 people, mainly gathered for services in churches which collapsed on them, another eminent theologian, Austin Farrer, said: “God’s will was that the elements of the earth’s crust should behave in accordance with their nature”. There is not much comfort there – nor (more importantly) much reason to believe in such a god.

So, finally, I want to come to the essential difference between science and religion.

What do we mean by religion? It started with attempts by primitive men to explain the mysterious and threatening world they lived in. They saw the world as inhabited by many powerful spirits, and they tried to appease them with sacrifices. Once you found that if you carried out some ritual at the right date in the depths of winter, the sun began to come back and winter turned to spring, it was too risky to stop doing it every year. Once the Aztecs began human sacrifices of slaves and prisoners of war to their gods, they could not stop in case the gods turned against them.

And so we progressed from a world of many gods – it is clear from the Old Testament that the Jews started by believing in many gods – gradually unifying them. But the idea of preserving the community through carrying out the correct rituals survived, and it was entrenched because of the power it gave to the priests and kings. It was also reinforced because inevitably general rules of conduct and morality became attached to religion, and so in due course religion became the vehicle for much of mankind’s profoundest thought.

This is where we stand today. Religion offers comfort and community to some people, and it still helps sustain the power structure of society, but its factual claims about the nature of the world are generally given as little emphasis as possible – especially in external discourse – because they cannot be supported.

What do we mean by science?

First, science is not the same as technology or engineering. Medicines and detergents and fertilisers and refrigerators and computers are by-products of science but they are not science itself. Nor is science fiddling around in laboratories, doing experiments.

Science lies not in what scientists do but in the method they use for doing it. It is a way of knowing about the world – or, better, a way of diminishing our ignorance.

Science works by asking questions and proposing answers – “hypotheses”. These are often flashes of inspiration, as when Francis Crick and James Watson suddenly realised that the DNA molecule was a double, intertwined helix.

But that is not enough. The next step is to deduce or predict what the consequences of the hypothesis would be and to test the idea by finding out if these predictions actually are true. Only when all the consequences of your hypothesis you can think of have been tested and found to be true does your hypothesis become a theory – not a fact, because scientific answers are always provisional and open to revision.

Despite – or probably because of – this very cautious way of proceeding, science has proved to be the most powerful tool we have ever had for finding out about the world we live in. From the origins of the universe to the minutest fundamental particles inside the atom, it has delivered an internally consistent account that has stood up to the most rigorous testing, constantly evolving and being elaborated. If human enterprises are to be judged by their fruits, then science has proven itself beyond question.

And it has done so by maintaining doubt. At the end of the 19th century Isaac Newton’s laws of motion were so fundamental to all our understanding of the universe that they must have seemed fixed for eternity. But then along came Einstein and bent space and unified it with time. Lord Kelvin, one of the greatest scientists of the 19th century, worked out that the earth was only a million years old. But he was no creationist: he was calculating the time the earth would have taken to cool to its present state but without knowing anything about the way the earth’s heat was sustained by radioactivity within it. So scientific ideas can be wrong, but science is not the ideas but the method by which they are both proposed and then disposed of and the method by which they can be replaced by something more in conformity with what observation and experiment have found.

This is where science differs utterly from religion and is infinitely superior to it as an endeavour. Take some examples.

In the 17th century, two German scientists, Johann Becher and Georg Stahl, came up with a clever chemical theory to describe what happened when things burned. For a few decades stuff called phlogiston was thought to be given off in combustion, but eventually the theory was displaced by a better understanding of chemistry and phlogiston was relegated to history.

By contrast, Einstein’s theory of relativity predicted that – incredibly – time would go slower the faster you moved through space. The effect would be absolutely minute, but eventually when atomic clocks were accurate enough and aircraft fast enough, the experiment was done and the clock that went up in an aircraft was found to have moved on slightly less than the one left on earth. If the clocks had shown no difference, the theory would have had to be altered or even abandoned.

Similarly, in subatomic physics and in cosmology, the theoreticians are way in front of the experimenters. Time and again, they have predicted the existence of new subatomic particles which much later have usually – but not always – been found to exist in experiments using atom-smashers – the huge cyclotrons which collide atoms together and observe the bits they break into. Similarly, the existence of the planet Pluto was predicted long before it was actually observed, and the same happened with black holes.

This consistent, rigorous method applied in all areas by scientists has led to its huge success. It is not just that it has produced spectacular results in so many areas: except at the absolute leading edges where science is still somewhat speculative, the whole story hangs together in a consistent, coherent description of how things work. Such success is unprecedented in the history of mankind.

What would be the equivalent enterprise in religion? When has religion ever predicted something for which a careful test could be made? Well, Jesus predicted the end of the earth within the lifetime of his hearers. (12) Did they abandon his theories when this prediction turned out to be false? No. And ever since, priests and cults have been predicting the end of the world, naming date after date. What happens then? They are proved wrong. Do the millennialists change their beliefs? No way! They simply go quiet for a while and then make a new prediction.

Even more fundamentally, given that Islam and Hinduism and Christianity and so on are all incompatible with each other, can their believers propose any objective test to distinguish which religion is true? Of course not, because their religions are based on accepting their claims without question on the unproven authority of sacred books or the teachings of prophets.

Religion is about certainties, and doubt is destructive. Science is about uncertainties and doubt is fundamental. When you ask a scientist what would convince him that a theory was wrong, he can answer easily. When you ask religious believers what would convince them that their belief was mistaken, they generally say “nothing”.

That does not indicate reasonable belief. It is belief at best without evidence and at worst in the face of the evidence. And yet believers tend to regard such unreasonable belief – faith – as especially virtuous. It is better regarded as wrong and dangerous. Ambrose Bierce, the American satirist (d. 1914) defined faith as:

belief without evidence in what is told by one who speaks without knowledge of things without parallel (The Devil’s Dictionary).

Mathematician and educator W.K. Clifford (1845-1879) said:

It is wrong always, everywhere, and for anyone, to believe anything upon insufficient evidence. (Ethics of Belief)

And Voltaire said all too truly:

People who believe absurdities commit atrocities.

– the old idea of good men possessed by bad ideas.

Richard Robinson, an Oxford philosopher who died a few years ago, went further, and I want to end with a quotation from his book An Atheist’s Values:

According to Christianity one of the great virtues is faith. . .

According to me this is a terrible mistake, and faith is not a virtue but a positive vice. More precisely, there is, indeed, a virtue often called faith but that is not the faith which the Christians make much of. The true virtue of faith is faith as opposed to faithlessness, that is, keeping faith and promises and being loyal. Christian faith, however, is not opposed to faithlessness but to unbelief. It is faith as some opposite of unbelief that I declare to be a vice. . .

Christian faith is not merely believing that there is a god. It is believing that there is a god no matter what the evidence on the question may be. Have faith, in the Christian sense, means ‘make yourself believe that there is a god without regard to evidence.’ Christian faith is a habit of flouting reason in forming and maintaining one’s answer to the question whether there is a god. Its essence is the determination to believe that there is a god no matter what the evidence may be.

Therein lies the difference between science and religion.


Note 1: Hymn of the Flagellants – see Ziegler p.73

Note 2: It was recommended by Sir William Osler in the 1923 edition his Principles and Practice of Medicine –

Note 3: Act 5, Scene 1

Note 4: The spheres make another appearance in The Merchant of Venice [Act 5, Scene 1]:

“There’s not the smallest orb which thou behold’st
But in his motion like an angel sings,
Still quiring to the young-eyed cherubims.

Note 5: Confessions, quoted in Koestler pp. 90-91

Note 6: Koestler, p.105

Note 7: See

Note 8: Cadbury p.307

Note 9:

Note 10: Except, he says, for explicit miracles such as the resurrection of Jesus Christ.

Note 11: David Hume, following Epicurus, presented this classic problem in the form of a trilemma: “Is he [God] willing to prevent evil, but not able? then is he impotent. Is he able, but not willing? then he is malevolent. Is he both able and willing? whence then is evil?” – Dialogues concerning Natural Religion, part X.

Note 12: Mark 13.30.



Arthur Koestler – The Sleepwalkers: A History of Man’s Changing Vision of the Universe (Arkana)

J D Bernal – The Extension of Man (out of print)

Roy Porter – Enlightenment – Britain and the Creation of the Modern World (Penguin)

Philip Ziegler – The Black Death (Penguin)

Deborah Cadbury – The Dinosaur Hunters (Fourth Estate)

Karen Armstrong – A History of God (Heinemann)

A N Wilson – God’s Funeral (John Murray)

Richard Robinson – An Atheist’s Values (Oxford, & on Internet at )

Lewis Wolpert – The Unnatural Nature of Science (Faber)

Richard Dawkins – Unweaving the Rainbow (Penguin)

Jared Diamond – Guns, Germs and Steel (Vintage)

Matt Ridley – The Origins of Virtue (Penguin)