Rite and Reason: He discovered oxygen, was a founder member of the Unitarian Society, and was eventually forced to leave England. Brian Mayeremembers an exceptional, if mostly forgotten, man.
Joseph Priestley (1733-1804), who died 200 years ago next Friday, was an extraordinarily gifted man. He has been called the father of modern chemistry, had a major influence on the development of political science and was also a learned theologian.
Born at Fieldhead in Yorkshire, the son of a draper, at school he became proficient in physics, philosophy, mathematics, and a number of languages. He was trained for the Presbyterian ministry at Daventry Academy in Northamptonshire, where he read David Hartley's Observations of Man and was deeply influenced by its views on free will and the idea of human perfectibility through education.
While serving as a minister, he opened his own school to develop his ideas on education and especially how science could improve the quality of human life. He also founded an irregular periodical Theological Repository in which he expressed views that aroused considerable controversy.
Priestley favoured the autonomy of the individual congregation, saw no objection to the proliferation of sects, attacked the principle of an established church and demanded complete toleration for Roman Catholics.
His first published work was The History and Present State of Electricity (1767), where he argued that the history of science was important for showing how human intelligence discovers and directs the forces of nature.
The following year he turned his attention to politics and published An Essay on the First Principles of Government.
This contained the following idea, remarkable for its time and later developed by Jeremy Bentham: "The good and happiness of the members, that is the majority of the members of the state, is the great standard by which everything relating to that state must finally be determined."
Through these books Priestley became friendly with Benjamin Franklin, who encouraged his work in science and politics. In 1774, Priestley wrote The State of Public Liberty in General and of American Affairs in Particular, which attacked the British government for depriving the American colonists of their rights and liberties.
If his books on politics made him unpopular with the British government, his theological works didn't endear him to church leaders. A History of the Corruptions of Christianity (1782) and A History of Early Opinions concerning Jesus Christ (1786) put forward his ideas on Unitarianism.
They attacked such doctrines as the virgin birth and the Trinity, and denied the infallibility and accepted impeccability of Jesus, although Priestley always held to the belief that Jesus was the Messiah.
He moved to Birmingham and became friendly with businessmen and scientists like Josiah Wedgwood and James Watt. Although his scientific work, such as his famous discovery of oxygen in 1774, proved popular, his political and religious views were constantly drawing fire down on him.
He became one of the leaders of a group of men that became known as Rational Dissenters and, in 1791, a founder member of the Unitarian Society.
The same year, he wrote a pamphlet defending the French Revolution, in which he expressed the belief that developments in France made "universal peace and goodwill among all nations" more likely.
He also predicted that the revolution heralded a change in the role of monarchy and that in future monarchs would be the "first servants of the people and accountable to them". Not surprisingly, these sentiments did not endear him to George III.
Tories in Birmingham made inflammatory speeches attacking Priestley's political views, as a result of which a mob destroyed his house and most of his papers (some of which had not yet been published), books and scientific equipment.
He moved to London but further hostility made him decide to emigrate to America in 1794, where he settled in Pennsylvania.
As founder of the first Unitarian church in America, his sermons were attended by the then vice-president, John Adams. But Priestley supported Adams's opponent, Thomas Jefferson, who greatly admired and consulted him.
He continued to write and publish, mainly on Unitarianism, right up to the time of his death. Before he died, he had all his children brought to his bedside and, after prayers, exhorted them to love each other and to continue to work for the advancement of mankind.
Joseph Priestley was remarkable for his breadth of learning, certainly, but even more so for how much so many of his views were in advance of his time. He also displayed a welcome tolerance in an age that was far from tolerant and in which differences of creed and opinion so often led to discrimination and bloodshed. Two hundred years after his death, such a person surely deserves to be remembered.
• Brian Maye is a writer and historian