Who is in this series

Every life in this series answers the same question: what made this person stop believing, or never start, and how did that unbelief show itself and change over the years? To answer it, we first had to decide whose unbelief counts. This page sets out the rule we used, the evidence we accepted, and the people we left out and why.

The rule

A person is included if, in their own words, they did not believe in a God who knows and cares about human beings: a God who hears prayer, who judges, who rewards and punishes, who guides history, or who promises a life after death.

That rule takes in a wide range of people. Some said plainly that there is no God. Some said that whether God exists cannot be known. Some held that gods might exist but take no interest in us, or used the word God for nature itself, or believed in a creator or a power behind the order of nature that pays no attention to any one of us. Each of them is marked with a label, and what each label means is set out under "The labels".

It does not matter whether a person lost a faith or never had one. People raised without religion are included if they wrote or spoke about their unbelief. It does not matter, either, if a person later changed their mind and returned to belief: Annie Besant became a Theosophist, and Ayaan Hirsi Ali became a Christian. Their unbelief was real while it lasted, and the change is part of their story.

The evidence

We judge by the person's own words: their books, essays, letters, diaries, speeches and recorded interviews. Private writing counts as much as public writing, and is often the better evidence, because it was not written for an audience. Mark Twain's views on God are known chiefly from papers he kept back from publication, and that does not make them less his.

Where a person's own words do not survive, we rely on what others reported, and we say who they were. For several ancient lives, the only witnesses are later writers, some of them hostile. For a few people, the only evidence of unbelief comes from their accusers: informers, prosecutors or refuters. They carry the label "accused", and their chapters weigh what the accusers had to gain.

Where the sources disagree about what someone believed, the chapter says so and gives both accounts.

Who is left out, and why

The rule leaves out some famous names that many readers will expect to find here. Each of them rejected the authority of a church or of scripture, and many were called infidels or atheists in their own day, but their own words show that they believed in a God who cares for human beings.

• Voltaire spent his life attacking the Church, but he called himself a theist, argued against the atheists of his day, and refused in his poem on the Lisbon earthquake to accept an indifferent God. He died writing that he adored God.
• Thomas Paine opened The Age of Reason with "I believe in one God, and no more; and I hope for happiness beyond this life," and wrote it in part to stop France from sliding into atheism.
• Elizabeth Cady Stanton rejected the authority of the Bible but kept a reverence for "the great Spirit of All Good."
• Robert Taylor, twice jailed for blasphemy, told his jury that he was "in my heart and soul a Deist," and served as chaplain of a society founded for "the public worship of Almighty God."
• Abu al-Ala al-Maarri doubted revelation, but in his poems he professed one God and told his followers to pray and give alms.
• Matilda Joslyn Gage attacked the Church's teaching on women, but never lost her belief in God.
• Omar Khayyam's own prose prays to God; the doubting quatrains that made his name cannot be shown to be his.
• Giulio Cesare Vanini was burned as an atheist, but his own books defend God and Providence; "atheist" was his judges' word.
• Abdullah al-Qasemi went from defending Wahhabi orthodoxy to putting God on trial in his late books, but in 1963 he wrote that he did not doubt God, and that his attacks were aimed at tyrants and idols set up in God's name.
• Faraj Foda argued for a secular state, but he wrote as a Muslim throughout.
• Tevfik Fikret wrote verse attacking religion and war, but in his own reply to his critics he called himself a believer.

Their stories are told briefly in the chapter "Near the Line". Several of them still appear in this series, in the lives of the people who read them. Richard Carlile went to prison for printing Paine's Age of Reason, and Charles Bradlaugh and Robert Ingersoll praised it; Voltaire was read by many of those who came after him.