What turned them
What first made each person stop believing, or never start? The answer comes from each chapter and its sources, and many lives have more than one. Where the sources do not say, we say so rather than guess.
Each life carries one main reason and up to two others. The short account under each name says what the chapter says, with the same hedges; follow the name for the whole story and its sources. For what each person came to believe, rather than what started it, see Labels.
All 133 lives, each shown once under its main reason.
The doctrine of hell
Eternal punishment could not be squared with a good God.
- Robert G. Ingersoll 1833–1899
A sermon on hell left a scar, and in his twenties he took the creed apart by reading Paley, Volney, Gibbon and Paine.
- Andrew Carnegie 1835–1919
A circle of friends in the 1850s voted down dogmas such as predestination and infant damnation; Spencer and Darwin later gave him a philosophy in place of theology.
- Taslima Nasrin b. 1962
By her memoir's account, as reviewers report it, she decided as a child that a God who roasts people alive was cruel; she said science training later made her an atheist.
- Ayaan Hirsi Ali b. 1969
By her own account she could not fit the burning of unbelievers with a merciful God, and in 2002 she said aloud she did not believe, free of fear of hell.
A loss or suffering
A death or a suffering that a loving God should have prevented.
- Vissarion Belinsky 1811–1848
After his friend Stankevich died in 1840 he wrote that he still wanted to believe and could not; it is the first loss the sources tie to his unbelief.
- Annie Besant 1847–1933
By her own account, weeks of her baby's suffering in 1871 struck the first blow at her belief in a merciful God, after a harmony of the Gospels had planted a doubt.
- Marie Curie 1867–1934
Her daughter Eve wrote that her mother's death when Marie was ten stirred a revolt against God; Marie herself never explained, so this account rests on her biographers.
- Leo Igwe b. 1970
By his own account, a grieving woman's question at a funeral began a crisis of faith, which his seminary study of the arguments and of Paul Kurtz carried further.
Scripture that did not add up
The sacred text or the teaching contradicted itself, or failed when read through.
- Uriel da Costa c. 1585–1640
Dreading damnation, he despaired of the Church's rules for salvation, then found the Law of Moses silent on an afterlife and, he concluded, contradicting the law of nature.
- Jeremy Bentham 1748–1832
In his own later account, examining the Thirty-nine Articles at Oxford he found no meaning in some and meanings irreconcilable with reason in others, then signed them anyway.
- Charles Darwin 1809–1882
After the Beagle voyage he reasoned that the Gospels differed in detail and that miracles grew less credible as natural laws became known, and disbelief crept over him slowly.
- Ernestine Rose 1810–1892
As her admirers told it, a devout rabbi's daughter asked questions about creation and evil that went unanswered, and renounced the Bible at fourteen.
- Ernest Renan 1823–1892
Learning Hebrew and reading the Bible as any ancient book, he found that a text claimed as inspired had only to be wrong once, and he left the seminary in 1845.
- Charles Bradlaugh 1833–1891
At fourteen he found the Thirty-nine Articles and the Gospels disagreed, was answered with a threat, and then read Robert Taylor's Diegesis while arguing with freethinkers.
- Mark Twain 1835–1910
As a grown reader he found he could not pretend the Bible was the word of God, and he could not square eternal punishment with a good end.
- Friedrich Nietzsche 1844–1900
At school at Pforta he learned to read the Bible as an ancient book, and in 1865, after reading Strauss, he told his family he would investigate rather than believe.
- Madalyn Murray O'Hair 1919–1995
By her own later account she read the whole Bible in one weekend as a girl and found it repugnant, though her son's account is less tidy and accounts differ.
- Penn Jillette b. 1955
By his own account, at sixteen he read the Bible from cover to cover, was appalled by its contradictions and by God telling Abraham to kill his son, and called himself an atheist.
- Seth Andrews b. c. 1968
Moved by a Hitchens video and by what he saw of churches as a broadcaster, he read the Bible without a filter in his late thirties and could not sustain it.
- Matt Dillahunty b. 1969
Studying to rebuild his faith after a job loss in 2001, he found reason destroyed it; one stage was an internet argument over God sending bears to kill children in Kings.
A lie caught out
A trick, a fraud or the conduct of the faithful gave the game away.
- Voltairine de Cleyre 1866–1912
In a convent school, told to obey without feeling what she said, she answered "I will not lie"; she lived in fear of damnation, and left a freethinker.
- Chen Duxiu 1879–1942
No lost faith is recorded; as a boy he drove off a kinsman who claimed to carry money to the dead, and later demanded thought that was scientific, not imaginative.
- Ricky Gervais b. 1961
By his own telling, at about eight his mother's reaction to his brother's question made him decide she was hiding something; reading, which he never names, followed.
A book or a teacher
A particular author or teacher opened the question.
- Baruch Spinoza 1632–1677
Accounts differ, but he read Maimonides, Ibn Ezra and Descartes, and came to think the rabbis' doctrines rested only on their own authority.
- Claude Adrien Helvétius 1715–1771
At his Jesuit college he read Locke's Essay, which his biographer says made a revolution in his ideas; it is the only dated cause the sources give.
- Abner Kneeland 1774–1844
Doubts about Bible stories like Jonah first ended in reassurance; a hostile colleague says Priestley's materialism and later reading in Philadelphia made the doubt last.
- Arthur Schopenhauer 1788–1860
Brought up in a formal, unfelt religion, he was taught by Schulze to read Plato and Kant, wrote against Schleiermacher that philosophers are not religious, and found the Upanishads.
- Richard Carlile 1790–1843
Carlile, by his own 1819 account, lost his faith on reading The Deist and Paine, after the charge of blasphemy against Hone's parodies disgusted him.
- Percy Bysshe Shelley 1792–1822
At Oxford he read Locke and Hume and found the sceptical argument unanswerable; his father's attack and the loss of his cousin's love then turned doubt into open atheism.
- Frances Wright 1795–1852
In her own account, study, reading and reflection answered the questions a devout child had asked, and the Greek philosophers, above all Epicurus, made her an Epicurean.
- Ludwig Feuerbach 1804–1872
Studying theology under Daub and then hearing Hegel, he found religion absorbed into philosophy until, in 1825, he told his father he could study theology no longer.
- Karl Marx 1818–1883
At nineteen, reading Hegel in Berlin dissolved the idealist gods he had held; Feuerbach's book then convinced his generation that God was human nature projected into heaven.
- Ignacio Ramírez 1818–1879
As a boy he devoured the forbidden books in a cathedral library, then read for eight years at San Gregorio; schoolfellows called him the Voltaire of Mexico.
- George Eliot 1819–1880
In 1841 she met the freethinking Brays in Coventry and read Charles Hennell's Inquiry into the origin of Christianity, which her husband thought hastened the change.
- Leslie Stephen 1832–1904
Reading Comte and Kant while a Cambridge tutor, he became convinced that Noah's flood was fiction and that he had never really believed it.
- Thomas Hardy 1840–1928
Essays and Reviews, Darwin and an 1865 reading of Newman, whose reasoning, he found, had no first link, undid the faith of a boy who meant to be a parson.
- Thomas Edison 1847–1931
By his own memory written decades later, finding Paine's writings on his father's shelf at thirteen was a revelation; he never called himself an atheist.
- Kōtoku Shūsui 1871–1911
No faith of his own is recorded; as a pupil of the thinker Nakae Chomin he took up a morality without God, which he defended in 1901.
- Bertrand Russell 1872–1970
By his own account he gave up the First Cause argument at eighteen on reading Mill's Autobiography and its question, Who made God?
- M. N. Roy 1887–1954
A later scholar says a reply in New York about the masses' poverty and Borodin's teaching in Mexico turned him from spiritual nationalism to Marxism; accounts differ on which mattered more.
- Hu Shih 1891–1962
As a boy raised among Buddhist devotions, he read Sima Guang's history and Fan Zhen's argument that the spirit dies with the body, and in his telling became an atheist.
- Bhagat Singh 1907–1931
By his own account, a crisis in his party sent him to study Bakunin, Marx and Lenin, and by the end of 1926 he no longer believed in God.
Science
Evolution, astronomy, medicine or physics offered a natural explanation.
- Julien Offray de La Mettrie 1709–1751
In Frederick the Great's account, a fever at the siege of Freiburg in 1744 showed this physician that thought depends on the body; his medical training under Boerhaave may also have helped.
- Baron d'Holbach 1723–1789
His biographer infers that translating German geology showed him the Flood could not explain the strata, which led him to doubt the sacred records; no letter of his says so.
- Yamagata Bantō 1748–1821
Studying European astronomy with Osaka astronomers, he came to trust measurement over tradition and argued there are no spirits, though no source dates his turn.
- Ludwig Büchner 1824–1899
No source records when he stopped believing; his biographers say the physician's materialism grew from his medical studies, Moleschott's book and the quarrel over the soul between Vogt and Wagner.
- Ernst Haeckel 1834–1919
His faith wore away between 1855 and 1857; the editor of his letters names his science, his teachers, his friends and human misery.
- W. K. Clifford 1845–1879
A friend did not know when or how his High Church faith gave way; the Dictionary of National Biography says reading Darwin and Spencer dispelled it.
- Luther Burbank 1849–1926
In his telling, Darwin's book and the uproar against it pushed him out of his Baptist upbringing, and he called a good God sending people to hell utterly damnable.
- Albert Einstein 1879–1955
At twelve, popular science books convinced him that much in the Bible could not be true, ending his deep religiosity, as he wrote in his 1946 autobiographical notes.
- Lu Xun 1881–1936
The old doctors who failed his father looked like fraud once he read Huxley and studied medicine; only in 1936 did he say he was certain there are no ghosts.
- Jawaharlal Nehru 1889–1964
His boyhood Theosophy faded without a crisis, and by his account the assurance of his natural-science studies at Cambridge grew up in its place.
- Luis Buñuel 1900–1983
At about fourteen he began to doubt Hell and the Last Judgment, and he wrote that reading Darwin's Origin of Species at seventeen made him finish losing his faith.
- Ismail Adham 1911–1940
By his own account, he read Darwin and Haeckel before thirteen, resisted forced Islamic rites, and told his father he was a Darwinian; his life story rests on his word.
- Richard Dawkins b. 1941
At nine he doubted why he should believe one of many contradictory religions; at fifteen or sixteen a friend persuaded him that Darwin explained design, ending his last belief.
Injustice they saw
Caste, poverty, persecution or oppression done in religion’s name or with its blessing.
- Jean Meslier 1664–1729
By his own account he was never of light belief, and from his youth he saw the evils and injustice of the world as proof against a good, wise God.
- Mikhail Bakunin 1814–1876
After Dresden's radical reading he still believed in God; the open break came in the 1860s in his fight with Mazzini, who joined God to nation.
- George Holyoake 1817–1906
By his own account and his biographer's, it was his friend Charles Southwell's prosecution for blasphemy in January 1842 that ended his belief, not the church-rate quarrel of his boyhood.
- Emma Goldman 1869–1940
Raised in a household that kept the rites but rarely spoke of belief, she turned from authority through pity for the hanged Russian revolutionaries and the Haymarket executions.
- E. V. Ramasamy (Periyar) 1879–1973
By his own later account, his doubt began when his family called other castes and faiths polluting, and the holy men he met seemed hollow; Kashi hardened it.
Argument and evidence
Reasoned out over time, rather than set off by one event.
- Protagoras c. 490–420 BCE
His one surviving sentence gives two reasons: the obscurity of the question and the shortness of life. No source names an event or a date.
- Epicurus 341–270 BCE
By one ancient story, at fourteen he asked his schoolmaster where Hesiod's Chaos came from and got no answer; accounts differ, and he never denied the gods.
- Wang Chong 27–c. 97
Reading widely, he found much in the books and sayings of his day he could not accept, and he weighed each claim, from ghosts to thunder, against what could be observed.
- Fan Zhen c. 450–c. 515
He argued that spirit is only the working of the body, and wrote the essay, he said, because the monks and temples were draining the wealth of the poor.
- David Hume 1711–1776
Before he was twenty, by his own account, doubts stole in while he was trying to prove the common opinion; the letter names no book, teacher or event.
- Denis Diderot 1713–1784
A partisan disciple said mathematics in Paris bred his contempt for theology; by 1749 his blind-man argument had undone the argument from design, though he still said he believed.
- Harriet Martineau 1802–1876
By her own account, the doctrine of Necessity wore her faith away over many years, deaths of friends at Tynemouth pressed her further, and a journey through the East finished it.
- Thomas Henry Huxley 1825–1895
In his own telling, a boyhood essay on the limits of knowledge and later the methods of science left him unable to claim what he could not show.
- G. W. Foote 1850–1915
In his own one paragraph he read and thought for himself in Plymouth and passed gradually through stages of scepticism, naming no single event or date.
- Shibli Shumayyil 1850–1917
In Paris the popular materialism then in vogue uprooted his childhood religion, by his own recollection; a question about the cause of his first cause removed the last place for God.
- Zora Neale Hurston 1891–1960
As a child she could not love an unseen God on demand, and puzzled that the saved still sinned and died; college study of the world's religions revived the questions.
- Abraham Kovoor 1898–1978
By his own account, studying science at Calcutta taught him to question miracles and prophecies, and he could not accept the Bible as the word of an all-knowing god.
- Goparaju Ramachandra Rao (Gora) 1902–1975
As a young botanist he lost faith in the packet of holy ash he carried for luck, which he later called the beginning of his atheism; years of reading scripture convinced him people had made God.
- Barbara Smoker 1923–2020
After the war her theological doubts grew, and by her account the more she read Catholic apologists and philosophers to shore up her faith, the less she could believe it.
- Christopher Hitchens 1949–2011
By his own telling, at about nine he knew his teacher had it backwards about the green grass, and by thirteen he saw religion as wishful thinking.
- Douglas Adams 1952–2001
At about eighteen he decided religious arguments failed the standards of proof he had learned at school; in his thirties Dawkins's books on evolution made him an atheist.
- Aron Ra b. c. 1962
He doubted the Bible literally from childhood; at nineteen, told to keep telling himself it was Jesus, he asked how he could know it was real, and stopped believing.
- Sean Carroll b. 1966
By his account no single event did it: he drifted from a mild childhood faith through many little things, and at Villanova he first said he was an atheist.
- Hemant Mehta b. c. 1983
He wrote that doubts began in high school, when his Jain parents' religion could not stand harder scrutiny; he names no book, person or event that set them off.
- Mubarak Bala b. 1984
By his own account, childhood questions about Allah, wide reading in science and a reading of the whole Qur'an led him slowly to atheism; his tellings of the final step differ.
Raised without faith
A freethinking or secular upbringing left no faith to lose.
- John Stuart Mill 1806–1873
His father brought him up without religious belief, on moral grounds, so that, as he wrote, he had not thrown off belief but never had it.
- Clarence Darrow 1857–1938
Raised by a doubting father in a churchgoing village, he had no faith to lose; he later gave up the hope of an afterlife, undated, and built a philosophy of causes.
- Margaret Sanger 1879–1966
Her father, a freethinking stonecutter who admired Ingersoll, taught her to question; she never told a story of losing a faith.
- H. L. Mencken 1880–1956
He grew up in a Baltimore family indifferent to religion for two generations, was confirmed without being taught to believe, and his biographer says he never knew a religious crisis.
- Virginia Woolf 1882–1941
She was never given a faith: her father had resigned his orders as an agnostic, and her mother wrote in defence of agnostic women.
- Diego Rivera 1886–1957
His father was a freethinking Freemason and his mother devout; he said he was an atheist from five or six, a claim no record documents.
- Jean-Paul Sartre 1905–1980
In his own telling, his grandparents' jokes and scepticism left a nominal faith that never took root, and at about twelve the thought that God did not exist simply came.
- Katharine Hepburn 1907–2003
Both her parents' families had left the church, so by the accounts she grew up in a house with no faith to lose.
- Albert Camus 1913–1960
In his novel's account, his family was Catholic only the way one is French, with four rites and no talk of God; no moment of loss is recorded.
- Richard Feynman 1918–1988
Raised in a Reform temple by an unbelieving father, at nearly thirteen he left Sunday school, seeing that the history he was taught mixed fiction with fact.
- José Saramago 1922–2010
In 2009 he said he had no religious education at school or at home and went through no religious crisis; the statement is his own, made late in life.
- Kurt Vonnegut 1922–2007
He grew up in a family of German-American freethinkers and said his ancestors were atheists, so he had no religion to lose and nothing to rebel against.
- Gloria Steinem 1934–2026
Raised among Theosophists with no single creed, she lost what little interest she had in religion on becoming a feminist, by a friend's account, seeing a God like the ruling class.
- Stephen Hawking 1942–2018
No source shows a religious upbringing; his parents taught him to ask science's questions, and as a schoolboy he watched his friends' faith with amused detachment.
- Salman Rushdie b. 1947
He came from a Muslim but mostly non-religious family, the son of an atheist; no moment of losing belief has been found, and his own accounts differ.
- Annie Laurie Gaylor b. 1955
She grew up without religion, with little talk of it at home, and her foundation calls her a third-generation freethinker; there was no faith to lose.
- Sam Harris b. 1967
By his own account his home was wholly secular, so religion was simply not an issue and there was nothing to rebel against; the attacks of 2001 made his unbelief public.
- Avijit Roy 1972–2015
A Hindu only by label, he grew up among his physics-professor father's books, which planted a seed of doubt, and by his brother's account Bengali writers deepened his student disbelief.
The sources do not say
What turned them is not recorded, or is known only from their enemies.
- Xenophanes c. 570–478 BCE
The fragments cannot be dated and do not say what made him criticise the gods of Homer and Hesiod; his travels among differing peoples are only a guess.
- Ajita Kesakambali fl. c. 500 BCE
We know one paragraph of his teaching, recorded by Buddhist opponents; the texts never say why he believed that nothing of a person survives death.
- Diagoras of Melos 5th c. BCE
No word of his survives; the only motive offered is a late Byzantine story that a man he trusted claimed his poem, swore it was his, and went unpunished.
- Prodicus of Ceos c. 465–395 BCE
Nothing records what Prodicus believed as a young man or any change of mind; only a theory of the gods' origin and a label survive in later reports.
- Critias c. 460–403 BCE
Nothing records what Critias believed; the one speech that makes the gods a human invention is spoken by a character, and scholars dispute whether he wrote it.
- Theodorus the Atheist c. 340–250 BCE
No source records a faith he lost or says why he denied the gods; we have only his training in argument and the name his enemies gave him.
- Euhemerus fl. c. 300 BCE
No source says what he believed as a young man or why he turned to the gods; ancient writers call him an atheist, and only his lost book's argument survives.
- Lucretius c. 99–55 BCE
No source says when or why Lucretius became an Epicurean; the poem shows only that he had, and that he followed Epicurus.
- Lucian of Samosata c. 125–after 180
No text says what turned him against the gods; he wrote of losing faith in philosophy, and late in life praised Epicurus for freeing people from fear.
- Jayarāśi Bhaṭṭa fl. c. 800
Nothing is known of his life, and no source says why a materialist turned on every school's means of knowledge; scholars offer only hypotheses.
- Ibn al-Rawandi c. 827–c. 911
What turned him is known only from his enemies, who offered wounded pride, ambition or money; none of his own books survives to say.
- Christopher Marlowe 1564–1593
He left no word about his own belief; every view put in his mouth comes from an informer, an enemy or a character in a play.
- Kazimierz Łyszczyński 1634–1689
No page in his own hand survives, and the only motive on record comes from the prosecution and the nuncio; he himself said his papers were a disputation, not belief.
- Matthias Knutzen 1646–after 1674
Nothing survives to say when or why he stopped believing; his enemies guessed at bad company or despair, and none of it is evidence.
- Andō Shōeki 1703–1762
No source records or dates his doubt; the Hachinohe museum only suggests, as conjecture, that watching farmers starve while samurai were spared turned the doctor toward thinking about society.
- Sylvain Maréchal 1750–1803
No childhood faith or crisis is recorded; his hostile biographer Germond says philosophy seduced him at the Collège Mazarin library, which is an opponent's explanation, not evidence.
- Constantin-François Volney 1757–1820
No source names a book or event; he went east to see where the opinions that govern us began, and came home treating religions as human works.
- Max Stirner 1806–1856
No source says when or why Stirner stopped believing; his first dated sign of distance from religion is in 1842, and the record before it is silent.
- Winwood Reade 1838–1875
No source records how he lost the Anglican faith of his early books; he later named Darwin and other thinkers as guides, and wrote against a God who made pain.
- Ambrose Bierce 1842–c. 1914
No document says what turned him; his brother recalls the boys resenting the revivalist atmosphere, and San Francisco colleagues remembered Kennesaw Mountain leaving a question in his mind.
- Manuel González Prada 1844–1918
How he lost his faith is unclear, since his 1871 verses and his 1917 recollection disagree; the lost war of 1881 turned him against the clergy.
- Sigmund Freud 1856–1939
The sources do not say when or why Freud stopped believing; they show only his later argument that religion is a wish carried over from childhood.
- Francisco Ferrer 1859–1909
No source records the day his faith went; his biographer thought the seeds were sown early, and by about twenty he was a Republican estranged from his family.
- E. M. Forster 1879–1970
No source records how or when he lost his faith; the loss falls somewhere between a religious family and the easy unbelief of King's College, Cambridge.
- Margaret Knight 1903–1983
In her third year at Cambridge, by one account, she gave up long-uneasy beliefs with relief; no source names what she read or what moved her.
- Ayn Rand 1905–1982
Her own account of how she came to unbelief has not been found; her heir says only that in her early teens she saw Communism as a secular religion.
- Simone de Beauvoir 1908–1986
At about fourteen she decided there was no God, her faith draining away gradually by her memoir's account; the sources name no single cause.
- Alan Turing 1912–1954
His friend's death in 1930 deepened his belief in survival after death, and the later atheism is dated only by his biographer, with no document for the change.
- Isaac Asimov 1920–1992
He said he was an atheist for years before he used the word, but what first turned him is not firmly sourced; accounts of his Orthodox childhood are second-hand.
- Steven Weinberg 1933–2021
No source shows any religious practice or belief in his childhood; the earliest sign of his unbelief is a theologian's worry about his lack of faith at Cornell.
- Carl Sagan 1934–1996
No source records a faith he lost; his teenage notebook shows a young scientist weighing arguments about God, and he later called himself agnostic.
- John Lennon 1940–1980
No record shows when or why he stopped believing; the earliest signs are second-hand remarks from 1964 and 1965, after a light Anglican upbringing.
- Daniel Dennett 1942–2024
Raised in a social, liberal Christianity, he told an interviewer in 2013 that as a teenager he simply realised he did not believe a word of it.
- Narendra Dabholkar 1945–2013
He wrote that he had long since lost belief in God but gave no year and no cause; no source records a childhood faith or the moment it ended.
- Stephen Fry b. 1957
Brought up in no faith, he loved the Anglican church at about thirteen; he later said he could not believe because he was fundamentally Hellenic, without saying when or why.