Seeing Joseph Priestley whole

Seeing Joseph Priestley whole

He’s more than just the discoverer of oxygen and soda water, and not just incidentally a Unitarian.

Patrick Page as Joseph Priestley in "The Mystery of Matter"

Joseph Priestley—portrayed by actor Patrick Page in the 2015 PBS documentary The Mystery of Matter—was a Unitarian minister and scientist. (© Jeffrey Dunn/Moreno/Lyons Productions LLC)

© Jeffrey Dunn/Moreno/Lyons Productions LLC


We are a species that looks at nature and sees patterns and meaning. From this perceived order we have come to interpret the world both scientifically and metaphorically, producing a variety of scientific disciplines on the one hand and theology and faith on the other. This distinctively human impulse to see both regularity and poetry in the universe presents us with a potential dilemma: Is one of these perspectives “truer” than the other, or do they both contain some share of truth?

The most influential answer to this question was offered in the late 1800s, and has shaped and constrained our interpretations ever since. Two books—History of the Conflict between Religion and Science by the chemist and historian John William Draper and A History of the Warfare of Science with Theology in Christendom by Andrew Dickson White—popularized the idea that science and religion are intrinsically contradictory views and inevitably lead to conflict. This conclusion has become powerfully entrenched in our culture in part because it has the effect of being a self-fulfilling prophecy: Once we look at history through the lens of conflict, it is easy to project adversarial motives onto past events. Moreover, the boundaries of science and religion have been redrawn based on this conflict thesis—we popularly define science to exclude supernaturalism and subjectivity, and some conservative religious movements view their faith as a fortress specifically against materialism and secularism. One of the reasons I treasure Unitarian Universalism is that we attempt to maintain a respectful curiosity for both science and religion, but maintaining this middle way is not easy in the midst of expectations that we choose sides.

The story of Joseph Priestley (1733-1804) is an excellent illustration of what is sacrificed when the search for knowledge is polarized in this way. The prolific English Unitarian minister, philosopher, scientist, and historian deliberately cultivated a broad and enthusiastic curiosity about the nature of the world and humanity’s place in it, and historians are still struggling to make sense of his great, sprawling life through the blinders of our modern assumptions. Priestley is generally remembered among American Unitarian Univer­salists as the discoverer of oxygen and soda water, who incidentally happened to be a Unitarian clergyman and came to the United States after his home and papers were burned in political riots. However, our English Unitarian kin remember him as one of their founders and have a fuller sense of his accomplishments; they could point out how central his religious identity and political views were to his scientific legacy, as well as his general renown, which deserves to be greater.

Interpreting historical events by our current standards and values is an approach to interpreting the past called presentism, which historians today strive to avoid. In the case of Priestley, a presentist approach holds up only those of his accomplishments that look like modern science. For example, we celebrate his role in the discovery of oxygen but dismiss his outdated theories of the hypothetical substance phlogiston, thought to be released during burning. Presentist history reduces the past to a clear, linear trajectory that leads directly to the present and disregards events, relationships, and forces that do not lie directly on that path. In Priestley’s case, it reduces his complex and fruitful career to that of a dabbler who insisted on pursuing a misguided theory but somehow stumbled into sharing the credit for one legitimate achievement.

Despite the destruction of his home and laboratory in the Birmingham Riots in 1791, Priestley left behind considerable documentation of his life and work, and many books have been written about him, usually focusing on one dimension of his life, such as scientific exploration or his political activity. Only at the end of the twentieth century did historians begin to appreciate the significance of his various interests and influence. The most authoritative work on Priestley is Robert Schofield’s two-volume biography The Enlightened Joseph Priestley, completed in 2004. Schofield gives special attention to the development of Priestley’s philosophy and its influence on his other areas of interest. However, a 760-page biographical interpretation of such a prolific and multifaceted personality may be more reading than most of us are willing to endure.

Two recent books about Priestley are more accessible. A collection of essays, Joseph Priestley: Scientist, Philosopher, and Theologian, is the first publication of the Dr. Williams’s Centre for Dissenting Studies at the University of London, edited by Isabel Rivers and David Wykes, the directors of the Centre. This volume helps us to appreciate the protean Priestley in seven essays, each exploring one dimension of his life and career: his passionate work as a Unitarian minister and teacher; his experimental activity, for which Americans best remember him; his efforts as a philosopher determined to be loyal to both materialism and Christianity; and so on. These essays give us detailed introductions to threads of Priestley’s life that Unitarian Universalists have tended not to appreciate, such as his contributions as a historian, especially a historian of science, and as a political philosopher and firebrand. While his significance in these areas may not come as news to most British Unitarians, I was impressed and moved by the integrity and passion he brought to bear in so many activities.

Much of the momentum for the Unitarian and Free Christian movements in England began in the Restoration era of the late 1600s, when legal statutes required increasingly strict conformity to Church of England doctrine. A diverse range of religious groups, collectively known as Dissenters, could not comply in good conscience with these statutes, and their members were barred from a variety of civic activities such as holding public office or gathering in groups of five or more. Priestley had been raised by his aunt Sarah Keighley after the death of his mother and, in addition to encouraging his intellectual growth, Keighley exposed him to a number of friends who counted themselves among these Dissenters. The young man took his religious beliefs quite seriously, and these skeptical figures, as well as his fervent theological study and personal reflection, led him far enough away from orthodoxy that he considered himself an Arian, believing that Christ the Son is subordinate to God the Father, who is the proper object of Christian worship. Further study as a teacher and then a Dissenting minister, in addition to his friendship with Dissenting theologian Theophilus Lindsey, led Priestley to embrace Unitarianism fully. Lindsey was himself supported and aided by Priestley in establishing the first explicitly Unitarian congregation in England, which began meeting at Essex Street in London in 1774.

Many in England at that time assumed that the philosophy of materialism, the belief that nature is composed only of matter, was incompatible with Christianity and necessarily led to atheism; Priestley was determined to prove them wrong. While his chemical, physical, and biological experiments demonstrated the usefulness of exploring the world on materialist terms, he rejected the example of many other materialists who jumped directly to a wholesale rejection of Christian faith. Instead, he advocated for a “primitive” Christianity uncomplicated by the innovation of a human soul separate from the divinely created natural world and its laws. Our mental activity is the product of a physical brain and naturally and consistently leads us to emulate ideas of right and wrong from our rearing and surroundings. The laws of nature, ordained by a benevolent God, compel us in a way that Priestley claimed preserves both Christian morality and human free will; in the same way he also deduced his political theory. Based on reason and natural experience, he concluded that citizens could assert the claim for natural rights and the exercise of civil liberties, a position that the British monarchy found explicitly threatening.

The standing order increasingly viewed him as a national threat, based on his growing reputation and his outspoken support of the American and French Revolutions, especially as the latter spun out of control. Priestley’s circle of Dissenter friends naturally felt a sense of recognition in the cause of civil and religious liberty and the promise of Enlightenment and republicanism, although many were alienated by the revolutionaries’ increasingly violent and corrupt behavior ostensibly in the service of these noble values. Having compared the clarifying power of reason to “laying gunpowder grain by grain under the old building of error and superstition,” Priestley’s radicalism could easily be denounced as a threat to Restoration England. In July 1791, on the second anniversary of the storming of the Bastille, a mob attack on a group of revolution sympathizers spread until they had looted and burned Priestley’s home and laboratory, the Unitarian chapel where Priestley served as minister, another Unitarian chapel called the Old Meeting House, a Baptist meeting house in nearby King’s Heath, and a third Unitarian chapel in Kingswood, as well as more than two dozen homes of congregational members they encountered on the way. Although Joseph and Mary Priestley narrowly escaped and relocated to another town, continued threats such as his burning in effigy convinced them to emigrate to the United States. He continued his work in philosophy, science, religion, and politics, but their isolation in Northumberland, Pennsylvania, hampered his full participation in these activities.

Looking back from the present day, when we have subdivided science into several disciplines, when we rankle at the misuse of religious sentiment in politics, when many assume science and religion to be intrinsically opposed, we would be inclined to ask which of his activities led him to be publicly reviled and threatened. Was it his radical philosophies? His heretical faith? His subversive politics? Herein lies the problem with presentist history about a figure like Priestley: The trends toward specialization and professionalization were in his time still relatively new; for a generalist like him, these activities were practically inseparable. If today’s assumptions about separate disciplines, professionalized vocation, and intrinsic conflict between science and religion are projected onto the past, we are sure to underestimate the interconnectedness and the significance of Priestley’s achievements.

This is precisely the weakness of the most popular recent book about Priestley, Steven Johnson’s The Invention of Air: A Story of Science, Faith, Revolution, and the Birth of America. A mix of popular history, popular science, and stream-of-consciousness brain candy, Johnson’s book may introduce many people to Priestley’s story, but it fails to offer a coherent picture of the man. The Invention of Airfalls into a popular current trend in history and science publishing in which a speculative approach takes the reader from topic to topic, sampling each like a hummingbird and connecting them in a way that hopefully strengthens our understanding of them all. It is possible to adopt this quirky style and do it well (Bill Bryson’s A Short History of Nearly Everything comes to mind), but it is much easier to do it poorly. Digressions about Marx and dinosaurs and coffeehouses and winning streaks in professional sports won’t disguise a misguided historical approach, for example. Whenever we read the phrase “there is no direct evidence, but it is entirely probable that . . . ,” we would be wise to keep our malarkey detectors at hand.

Johnson acknowledges the inaccuracy of presentist history, even as he is enthusiastically producing it. It is clear that he expects to look at the 1700s and find physicists and chemists and politicians and clergy in their modern form; when he does not, he concludes that Priestley’s diverse occupations are the sign of a sloppy dabbler. When Priestley publicizes his technique for producing carbonated water, as was the norm among experimentalists in his time, Johnson dismisses him as “a compulsive sharer.” A presentist interpretation steers us toward what historians now pejoratively call “Great Man history”—a smattering of intellectual celebrities occasionally sprouting up among the ordinary folk; I think we are better served by also recognizing the influence of external forces such as social trends, institutions, and significant relationships. The image of a 32-year-old Priestley stumbling suddenly onto an interest in science may make for dramatic reading, but overlooking the many thoughts, experiences, and connections that guided him toward experimentation makes for bad history.

What these two new books about Joseph Priestley accomplish is not so much the introduction of any new information as much as an affirmation of taking the broader view when we look to our past. My concern for the readers of The Invention of Air is not that they are reading an entertaining popular work of history and science; it is that they are accepting a fundamentally distorting portrayal of Priestley and of the eighteenth century in general. I know that not every layperson is prepared to tackle an academic work like Rivers and Wykes’s collection of essays, but anyone who reads even its excellent introduction will come away with a more accurate understanding of Priestley’s significance in his own time. I hope that we will see more work of this quality come from the Centre for Dissenting Studies. Their scholarship shines a light on the fascinating individual that Priestley was and reassures us that we aren’t likely to run out of interesting stories about this, one of our most committed and influential religious forebears.

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