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Nick Spencer

Darwin's Religious Beliefs

Nick Spencer

Nick Spencer is Director of Studies at Theos, the public theology think tank ( His book Darwin and God was recently published by SPCK (2009).

The following transcript can also be downloaded in PDF format (52KB)


"In my most extreme fluctuations I have never been an atheist in the sense of denying the existence of a God." [1] So wrote Charles Darwin to John Fordyce on 7 May 1879.

He died three years later, without changing his mind. "You have expressed my inward conviction," he wrote to the author William Graham in one of his last letters, "that the Universe is not the result of chance."[2]

No atheist, Darwin deliberately avoided bashing religion. "I hardly see how religion & science can be kept...distinct," he wrote to his friend, Brodie Innes, the vicar of Downe, "but...there is no reason why the disciples of either school should attack each other with bitterness." [3]

How is it, then, that this gentle, respectful, humane agnostic has become the patron saint of modern, aggressive atheism?

Perhaps, the modern, aggressive atheists reply, it is because Darwin also wrote to another correspondent in 1879, "Science has nothing to do with Christ." [4] Perhaps it is because he said the following year, "I do not believe in the Bible as a divine revelation, & therefore not in Jesus Christ as the son of God."[5] Perhaps it is because he said in his autobiography that, given that "the plain language of the text seems to [point towards]...everlasting punishment...I can...hardly see how anyone ought to wish Christianity to be true."[6]

The truth is that Darwin sits uncomfortably in both atheist and Christian camps. That is what makes him so interesting.

Darwin and religion

For someone who has had more impact on religious thinking than anyone else born in the last 200 years, Darwin wrote very little about religion. Mankind is famously absent from The Origin of Species and his only book to engage with Christianity in any detail (excluding his posthumously published Autobiography) is TheVoyage of the Beagle, in which he writes at some length and wholly positively about the work of missionaries in the South Pacific.

The reasons for his reticence are complex. Darwin did not want to upset his wife, who was devout. He did not want to upset public opinion in any way that might retard the reception of his theory. He generally approved of the religious influence on society.

One of his friends from his time on the Beagle was 2nd lieutenant Bartholomew James Sulivan, who was and remained a supporter of Christian mission. He and Darwin stayed friends and corresponded about missionary work in South America right up until Darwin's death in 1882, with Darwin being so impressed by what he heard that, later in life, he not only made regular small donations to the South American Missionary Society but even asked to be made an honorary member.[7]

Closer to home, when James Fegan, a local evangelist, requested use of a room in Downe village in 1880 to bring his tent revival meetings indoors, Darwin not only granted permission but told him:

"Your services have done more for the village in a few months than all our efforts for many years...Through your services I do not know that there is a drunkard left in the village."[8]

Perhaps most significantly, Darwin was a scientist, not a theologian or philosopher. "Dr Pusey [the Oxford divine] was mistaken in imagining that I wrote the Origin [of Species] with any relation whatever to Theology," Darwin once told the botanist Nicholas Ridley. [9] He was driven by a desire to understand and explain the natural world better, not to destroy, still less ridicule, people's religious faith. The immense popularity of The Origin of Species led him not to his own God Delusion but, rather, to a series of books on mankind, orchids and earthworms. Love of science, rather than hatred of religion, was what powered him.

None of this means that he had nothing of interest to say about religion (although he protested as much). Rather it reminds us that Darwin was, first and foremost, a supremely gifted natural scientist and not the kind of atheist pioneer he has, in some very different circles, become.

Darwin's upbringing

Like most people of his age and class, he was brought up a Christian. He came from sceptical stock. His maternal grandfather, Josiah Wedgwood, was a Unitarian, and his paternal one, Erasmus Darwin, made Josiah look positively orthodox. A disciple of the notorious French philosophes, worshipper of science, free thinker, he was also (at the time) Britain's most famous evolutionist, suggesting (vaguely) that life did not need a creator but arose "without parent by spontaneous birth."[10].

Despite such radical forbears and his own father's (probable) atheism, Darwin's upbringing was conventional. He briefly attended the local Unitarian chapel in Shrewsbury but when his mother died he moved to the parish church and thereafter to boarding school. Aged 16 he followed his brother, also called Erasmus, to Edinburgh where both were to study medicine, the family profession.

Neither took to it. Erasmus was never able to motivate himself and Charles was horrified by his experience of pre-chloroform operations and, in any case, already too interested in the study of nature.

Few letters survive from his Edinburgh days but those that do reveal, at best, a lukewarm religiosity. "Dear Charles I hope you read the bible", chided his sister, "and not only because you think it wrong not to read it." [11] "I often regret myself that when I was younger & fuller of pursuits & high spirits I was not more religious," she confided. [12]

Darwin's father was vexed by his son's lack of medical ambition and insisted he find useful employment. If medicine didn't suit him, then it had to be the church.

Early 19th century Anglicanism was a broad church and it would be an exaggeration to say that one needed a burning commitment to the gospel to be ordained. When, a few years later, Darwin's uncle, Josiah, was trying to persuade his father to allow Darwin to travel on the Beagle, he reasoned that not only would such a journey not be "in any degree disreputable to his character as a Clergyman", but that "the pursuit of Natural History" was in fact "very suitable to a clergyman"[13]. A serious personal belief in God was no bar to ministry but nor was it a necessity.

To his credit, Darwin hesitated and asked for time to reflect. Darwin read through some weighty theological tomes, such as John Pearson's Exposition of the Creed[14]and John Sumner's The Evidence of Christianity derived from its Nature and Reception,[15] and, duly persuaded and deeming himself "orthodox", agreed to ordination.

Darwin at Cambridge

There is little cause to doubt the reality of Darwin's "orthodoxy", although it is important to note what kind of orthodoxy it was. "Orthodox" for Darwin meant being able to assent to basic Christian doctrines. It was logical, objective, rationalistic, and demonstrable. Christianity was, first and foremost, a proof to be established.

Cambridge did little to change that, immersing him in the most influential theologian of the day, William Paley. Paley's Principles of Moral and Political Philosophy and Evidences of Christianity were compulsory at Cambridge, but it was his (optional) Natural Theology that most impressed Darwin. This transferred the arguments from physical design, which had proved so popular in the 17th and 18th centuries, into arguments from biological design.

Nature, Paley argued, contains "every manifestation of design". His book examined a vast range of these "manifestations", concluding that "design must have had a designer...That designer must have been a person [and] that person is God."[16] Darwin was impressed and Paleyian natural theology became a cornerstone of his faith.

Despite (or perhaps because) of this, Darwin's Christianity seems to have been no more secure in Cambridge than it had been in Edinburgh. His friend J.M. Herbert, who was also training for the ministry, recalled "an earnest conversation" with him "about going into Holy Orders". During the ordination service the Bishop would ask candidates, "Do you trust that you are inwardly moved by the Holy Spirit?" Herbert remembered Darwin asking him whether he could "answer in the affirmative" when thus asked. Herbert replied that he could not, to which Darwin replied, "Neither can I, and therefore I cannot take orders."[17]

Darwin and the voyage of the Beagle

It was perhaps because of this that when the opportunity arose of travelling the world on the Beagle, Darwin seized it. Between 1831 and 1836 Darwin was the self-financing, gentlemanly companion of Captain Robert FitzRoy.

FitzRoy is often remembered as a slightly ridiculous biblical literalist but he was, at the time, rather more open-minded. Indeed it was FitzRoy who did much to establish the modern science of metereology. He and Darwin discussed the latest geological theories, which were already being accommodated with a more nuanced reading of the opening chapters of Genesis.

Those conversations and his years on the Beagle did not seriously challenge Darwin's ordered, propositional, Paleyian Christianity but they did disturb its foundations.

When sailing up the west coast of South America Darwin experienced an earthquake and volcanic eruption, which shocked him. "A bad earthquake at once destroys the oldest associations," he wrote in The Voyage of the Beagle:

"the world, the very emblem of all that is solid, has moved beneath our feet like a crust over a fluid;-one second of time has conveyed to the mind a strange idea of insecurity, which hours of reflection would never have created."[18]

It seemed to suggest that the earth was indifferent rather than tailored to human needs. Perhaps the world was not as benign as natural theology assumed?

He also encountered people on the Tierra del Fuego who were shockingly barbarous, even animalistic. "I shall never forget how wild and savage one group appeared," he remarked.

"Four or five men came to the edge of an overhanging cliff; they were absolutely naked, and their long hair streamed about their faces; they held rugged staffs in their hands, and, springing from the ground, they waved their arms round their heads, and sent forth the most hideous yells." [19]

"A wild man is indeed a miserable animal", he remarked to a correspondent a few months later. [20]

Perhaps the line between humans and other species was thinner and more permeable than comfortable Anglican Archdeacons imagined?

Darwins' autobiography

When he returned to England in late 1836, he embarked on an extraordinary intellectual journey that, over the next three years, carried him into wholly uncharted territory.

His autobiography, written forty years later, concentrates his loss of faith into this period, and offers three broad reasons for that loss: doubts about the Bible ("no more to be trusted than the sacred books of the Hindoos"); moral objections (the Old Testament writers "attribute to God the feelings of a revengeful tyrant"); and philosophical problems ("the more we know of the fixed laws of nature the more incredible do miracles become.")[21]

Darwin undoubtedly stumbled over each of these issues but it is highly unlikely they all occurred to him during this period. For example, biblical criticism of the sort that was to scandalise and terrorise the Victorian mind had hardly made a mark in Britain by 1839. More probable is that Darwin fashioned his autobiography so as to bring together all his doubts into a single chapter and timeframe, which he placed during a period of intense and destabilising intellectual activity.

That activity resulted in his theory of evolution by natural selection. Darwin was a meticulous, almost obsessive note taker, and a series of notebooks from this period trace the development of his theory and the ways in which he worked to accommodate it with belief in God.

First, there was the problem of special creation. Evolution wrecked the idea that God had made each species separately. But then, was that such a great idea? Was it not "grander" to see all life emerging through a continuous process of law-governed evolution? How much more appealing was evolution than the idea "that since the time of the Silurian [God] has made a long succession of vile molluscous animals"?[22] Special creation was nothing to boast about. "How beneath the dignity of him, who is supposed to have said let there be light & there was light."[23]

In his own, fragmentary notes, Darwin was articulating the same view that Charles Kingsley would one day express more eloquently in a letter praising The Origin of Species, parts of which Darwin would subsequently include in the second edition of that book.

I have gradually learnt to see that it is just as noble a conception of Deity, to believe that he created primal forms capable of self to believe that He required a fresh act of intervention to supply the lacunas (or 'gaps') which he himself had made.[24]

Reconciling his new, evolutionary view of life with Christianity demanded more than this, however. Philosophically and aesthetically more satisfying as his theory of transmutation, as it was then called, may have been, Darwin recognized there were other issues.

In particular, there was the idea that humans may not, in fact, be that different from other species. "Man - wonderful man...with divine face turned towards heaven...he is not a deity, his end under present form will come...he is no exception", he wrote in Notebook C, sounding almost an Old Testament prophet.[25]

This upset human pride but there was more. What if key human attributes like thought, morality and religiosity, were not distinctively "spiritual" qualities but rather material outworkings of the evolutionary process? "Why is thought being a secretion of brain, more wonderful than gravity a property of matter?" he asked rhetorically.[26]

And if thinking could be reduced to the "merely" material, so could morality. Was morality merely an instinct too? Worse, was it an imperfectly formed and harmful instinct? "The mind of man is no more perfect than instincts of animals to all & changing contingencies, or bodies of either," Darwin thought. "Our descent, then, is the origin of our evil passions!!-The Devil under form of Baboon is our grandfather!"[27] If all this were true, it seemed to suggest that good and evil were not moral absolutes rooted in a spiritual realm, but primate attributes on which humans have stumbled.

Wedded to a worldview in which the material and the spiritual were necessarily distinct and opposed, this was a significant challenge. Where did it leave personal morality? Human conscience? The Last Judgment?

Finally, there was the question of suffering. This was not a new problem, as Darwin acknowledged, but it was newly significant. Evolution replaced Paley's "happy world... [of] delighted existence" with the brutal one of Thomas Malthus, in which a "dreadful but quiet war of organic beings [was] going on in the peaceful woods & smiling fields."[28] Suffering was a serious problem.

Religious proof

Such thoughts were unorthodox (to put it mildly) for the time and, not surprisingly, they shook a faith which owed more to the confident arguments of William Paley than it did to the shameful crucifixion of Jesus Christ.

The challenge was compounded by the fact that Darwin had never given much credence to feeling within religious faith. He was prepared, theoretically, to admit that reliable truth might be communicated through instinct or intuition, telling his young disciple George Romanes that "reason may not be the only instrument for ascertaining [theism's] truth." [29] But that was simply a theoretical admission, with little purchase on his own life. "I cannot put much or any faith in the so-called intuitions of the human mind," he wrote to Charles Lyell in 1874. [30] "I do not think that the religious sentiment was ever strongly developed in me," he admitted in his autobiography.[31]

His cousin, Emma Wedgwood, noted this in a letter sent a few months before their marriage.

May not the habit in scientific pursuits of believing nothing till it is proved, influence your mind too much in other things which cannot be proved in the same way, & which if true are likely to be above our comprehension.[32]

Darwin demanded the same kind and level of proof from his religion as he did from the species that he examined every day and, as such, was inevitably disappointed. Oddly, he appeared to recognise this himself, recalling in his autobiography how he "often invented day-dreams of old letters between distinguished Romans and manuscripts being discovered at Pompeii or elsewhere which confirmed in the most striking manner all that was written in the Gospels." "But," he continued, "I found it more and more difficult, with free scope given to my imagination, to invent evidence which would suffice to convince me." [33] No evidence would do for a mind that he latterly described as "a kind of machine for grinding general laws out of large collections of facts."[34]


That was pretty much how things stood when he closed his last notebook and married Emma in January 1839. He remained a theist, with Christian inclinations, but with little or no conviction or commitment. He made two sketches of his "species theory", in 1842 and 1844, and then shelved the manuscripts and turned to a monumental study of barnacles which lasted until 1854.

The reasons for Darwin's extended delay in publishing his theory have been much debated. The long-standing explanation has been that the theory was simply too controversial to have been published at the time. Whilst Darwinian evolution was a scientific rather than revolutionary or atheistic idea (unlike the more popular "evolutionary" ideas of the time) others are unlikely to have agreed with him. Indeed, that might have made it even more controversial.

When in October 1844, the publisher Robert Chambers anonymously published his book Vestiges of the Natural History of Creation, which presented to the world a comprehensive evolutionary view of creation, from astronomy to life to civilisation, he and his book were instantly and savagely criticised by learned men. "Mr Vestiges" was pilloried as "practical Atheist".

That said, more recently, John Van de Whye has argued that Darwin did not, in fact, intentionally delay publication but was simply busy analysing, writing and publishing the results of the Beagle voyage, whilst all the time constructing and testing his theory.[35] Moreover, recent studies of Darwin's life and work, have placed more emphasis on the continuity between his species sketches of the early 1840s and his subsequent work on barnacles, and thereafter seeds and pigeons.[36] These were not distractions from evolution but bulwarks in preparation. Darwin knew that he would need a mountain of evidence if his theory were to stand the intense and hostile scrutiny it was bound to receive, and he thus turned to a monumental monograph on barnacles, and thereafter his home experiments seed preservation and germination, to provide that evidence.

Either way, the species manuscripts were shelved; Darwin worked on with undiminished vigour and his health deteriorated. Since his return from the Beagle he had suffered from occasional bouts of vomiting, and these became more regular in the later 1840s. By way of cure he tried water-therapy, a mid-Victorian fad, travelling to a hydrotherapist in Malvern for a gruelling regime.

His eldest daughter, Annie, had also long suffered from ill-health and in 1851, he took her to Malvern before returning to Emma who was eight months pregnant. Two weeks later he received an urgent message. Annie had contracted a fever. Darwin returned instantly, to be faced with a changed child. "You would not in the least recognize her," he told Emma, "with her poor hard, sharp pinched features; I could only bear to look at her by forgetting our former dear Annie." [37]

The following week was the worst of his life. Annie rallied, then sank. She showed signs of recovery and then of fading fast. Unable to eat, she slowly wasted away. The doctors remained quietly confident. Darwin sat, holding her hand, alternately overjoyed and distraught. Eventually, she died, aged ten.

Most Victorian families lost children - Darwin himself lost two others in infancy - but Annie was his favourite and he had witnessed every last, degrading moment of her short life. The experience nearly destroyed him. It seems to have been the final straw in Darwin's gradual drift from faith. He wrote a short, painfully moving account of her life, and then never spoke about her again.

His theory of evolution had alerted him to the reality and apparent ubiquity of suffering but he could - or, at least, could try to - rationalise and cope with that. "From death, famine, rapine, and the concealed war of nature we can see that the highest good, which we can conceive, the creation of the higher animals has directly come," he wrote at the end of his 1842 species sketch.[38] The key question was did that "highest good" justify "the concealed war of nature". Darwin's tentative answer, at least in 1842, was 'yes'. But with Annie's death, suffering moved from being a theory to being horribly, painfully real. Whatever faith he had in the loving, just God of Christianity died with his daughter in Malvern.

The Origin of Species

Darwin was thus an atheist with regard to the Christian God but he was never an atheist in the full sense of the word. He remained a "theist" throughout the 1850s and '60s, although the God he believed in was now the God of first causes and, properly speaking, he was more deist than theist during this period.

The publication of The Origin of Species in 1859 put Darwin and his attitude to religion in the spotlight and even though he personally avoided that spotlight, we have clearer evidence for his religious opinions from this period of this life than any other.

He corresponded at length with Christian colleagues on questions of design, purpose, suffering and God. He wrote about humanity and its religious sensibilities in The Descent of Man. And he even responded to complete strangers who wrote asking him about his religious beliefs.

Although fluctuating throughout the period, he was, ultimately, happiest with the label agnostic, a word newly minted by his friend, Thomas Henry Huxley. "The mind refuses to look at this universe, being what it is, without having been designed," he wrote to Frances Wedgwood in 1861. "Yet, where one would most expect design, viz. in the structure of a sentient being, the more I think on the subject, the less I can see proof of design."[39] "I am driven to two opposite conclusions," he admitted to Henry Acland.[40] "My theology is a simple muddle," he told Joseph Hooker.[41]

Moreover, he was not simply agnostic in the sense of not knowing whether or not there was a God. He doubted whether the human mind, being evolved from that of a "lower" animal, could know such things. "Can the mind of man, which has, as I fully believe, been developed from a mind as low as that possessed by the lowest animal, be trusted when it draws such grand conclusions?" he wrote in his autobiography.[42] Not only did Darwin now know about God. He didn't know whether he could know.

Throughout all this, he was insistent that, as he told John Fordyce, "it seems to me absurd to doubt that a man may be an ardent Theist & an evolutionist."[43] Similarly, he disliked atheistic bullying. "Why should you be so aggressive?" he asked the atheist Edward Aveling in 1881. "Is anything gained by trying to force these new ideas upon the mass of mankind?"[44]

Darwin was never, despite what some of his modern devotees would like to think, an atheist. But nor was he a believer. A host of new ideas, natural selection among them, closed the door on the God of his early, Paleyian Christianity and his daughter's death nailed it shut. He died an agnostic but one with distinctive and well-formed, if openly confused opinions.

Ultimately, Darwin is too complex and too subtle a thinker to be either deified or demonised. As the historian John Hedley Brooke once observed, we should be careful not to pigeon-hole the man who wouldn't pigeon-hole pigeons.[45]


[1] Letter to John Fordyce, 7 May 1879

[2] Letter to William Graham, 3 July 1881

[3] Letter to J.B. Innes, 27 November 1878

[4] Letter to Nicolai Mengden, 5 June 1879

[5] Letter to F.A. McDermott, 24 November 1880

[6] Charles Darwin, The autobiography of Charles Darwin 1809-1882 (London: Collins, 1958; repr. Penguin, 2002), p. 50.

[7] My thanks to a former secretary of SAMS for this information.

[8] Letter to James Fegan, between December 1880 and February 1881

[9] Letter to Henry Ridley, 28 November 1878

[10] Erasmus Darwin, The Temple of Nature or, The Origin of Society (London, 1803)

[11] Caroline Darwin to Charles Darwin, 22 March 1826

[12] Caroline Darwin to Charles Darwin, 11 April 1826

[13] Janet Browne, Charles Darwin: Voyaging, Volume 1 of a biography (London: Jonathan Cape, 1995), pp. 153-156.

[14] John Pearson, Exposition of the Creed (London, 1659)

[15] John Bird Sumner, The Evidence of Christianity derived from its Nature and Reception, (London, 1821)

[16] William Paley, Natural Theology, (Oxford: OUP, 2006)

[17] Adrian Desmond and James Moore, Darwin (London: Penguin, 1992), p. 66.

[18] Charles Darwin, Voyage of the Beagle (London: Henry Colburn, 1839), p. 369.

[19] Darwin, Voyage, 2nd edition, p. 218

[20] Letter to William Fox, 23 May 1833

[21] Darwin, Autobiography, p. 85-96

[22] Charles Darwin, Notebook D, p.37.

[23] Charles Darwin, Notebook D, p.37.

[24] Charles Kingsley to Charles Darwin, 18 November 1859

[25] Charles Darwin, Notebook C, p.77.

[26] Charles Darwin, Notebook C, p.166.

[27] Charles Darwin, Notebook M, p.289.

[28] Charles Darwin, Notebook E, p.114.

[29] Letter to George Romanes, 5 December 1878

[30] Letter to Charles Lyelle, 3 September 1874

[31] Darwin, Autobiography, p. 91

[32] Emma Darwin to Charles Darwin, c. February 1839

[33] Darwin, Autobiography, p. 50

[34] Darwin, Autobiography, p. 85

[35] John Van de Whye, “Mind the Gap: Did Darwin avoid publishing his theory for many years?”, Notes and Records of the Royal Society (2007) 61, 177–205

[36] See, for example, Adrian Desmond and James Moore Darwin’s Sacred Cause: Race, Slavery and the Quest for Human Origins (London: Allen Lane, 2009)

[37] Letter to Emma Darwin, 19 April 1851

[38] Francis Darwin (ed.) The foundations of The Origin of Species. Two essays written in 1842 and 1844 (Cambridge: Cambridge University Press, 1909), p.52 [emphases added]

[39] Letter to Frances Wedgwood, 11 July 1861

[40] Letter to Henry Acland, 8 December 1865

[41] Letter to Joseph Hooker, 12 July 1870

[42] Darwin, Autobiography, p. 93

[43] Letter to John Fordyce, 7 May 1879

[44] Edward Aveling, The religious views of Charles Darwin (London: Freethought Publishing Company, 1883), p.5

[45] John Hedley Brooke, “Darwin and Victorian Christianity” in Jonathan Hodge and Gregory Radick (eds.), The Cambridge Companion to Darwin (Cambridge: CUP, 2003)