The royal physician and early member of the Royal Society died in London 400 years ago today.
Anna Winterbottom
Walter Charleton (1620–1707) has long been seen as the ‘barometer of his era’, registering the shift from magical to scientific thought. Four hundred years after his death, biographers have begun to rethink his contribution.
Walter Charleton. Image from the Royal Society.
Charleton was born in 1620 in Shepton Mallet. A committed monarchist, he was appointed physician to Charles I in 1643, having studied medicine at Magdalen Hall, Oxford under the natural philosopher John Wilkins.
Charleton’s best known treatises, The Darkness of Atheism Dispelled by the Light of Nature and Immortality of the Human Soul Demonstrated by the Light of Nature were published in 1652 and 1657, respectively. Charleton’s mixing of natural philosophy and theology, his sometimes controversial translations, including Epicurus’ Morals (1656), and his royalist sympathies may have led to his exile in Paris during the Commonwealth and Protectorate periods (1649–1660).
His loyalty was rewarded by the appointment to Charles II as Royal Physician during the King’s own exile. Charleton flourished in the atmosphere of intellectual renewal of the 1660s, joining the Royal Society in 1661 and being elected to the College of Physicians, acting as President between 1689 and 1691.
Harmonising systems of ‘natural philosophy’
By the early seventeenth century ‘natural philosophy’ — the idea that the world could be explained by the observation of nature rather than by reasoning using the principles of logic — was gaining popularity. However, there were still rival interpretations of how the laws of nature operated. Supporters of ‘mechanism’, like Thomas Hobbes, argued that matter — including humans and animals — was inert, being set in motion by forces or passions, the understanding of which was the key to natural philosophy.
Opposing this argument was the ‘atomist’ idea that matter was made up of tiny indivisible particles, each of which possessed its own motion. Some earlier supporters of the latter concept — such as Helmont and Paracelus, whose work Charleton translated in the 1650s — connected it with mysticism. Others, like Gassendi, whose theories Charleton was the first to introduce into English thought, harmonised the potentially radical atomist philosophy with Christianity by arguing that these tiny particles were finite and created by God.
As biographer Emily Booth notes, the ‘truly eclectic’ Charleton presented himself as ‘a syncretist rather than an innovator’. By translating philosophers from both sides of this contemporary debate and making use of both theories in his own work, he demonstrated that matter could possess the capacity for action and reaction, as well as being acted on by external mechanical forces. This was vital in the work of Charleton’s successors. For example, Newton employed a combination of mechanism and atomic principles in his theory of gravitation. Charleton’s openness to seemingly opposed theories thus helped to lay the ground for the development of a science in which theory was led by observation.
Medical musings
Charleton’s openness to different theories of the operation of the natural world led him to make some important suggestions about the workings of the human body, which he described as a ‘beautiful…Automaton: all whose parts are among themselves different in their sensible elements’.
In his 1659 Natural History of Nutrition, Life, and Voluntary Motion, he noted that the swelling observed in a tensed arm was the result of a mechanical process involving the muscle, rather than of an increase in the volume of bodily fluid as Cartesian theory had assumed. Enquiries into Human Nature (1680) also took an anatomical approach to processes like digestion. Perhaps most importantly, while he retained a belief in Galenic therapeutics, Charleton insisted on the importance of experimentation in medicine.
Charleton at the Royal Society
Charleton’s contributions to the Royal Society were also eclectic. He was the first to note both that the speed of sound changes according to the differences in humidity and temperature between day and night and that tadpoles become frogs. Many at the Society, including Robert Boyle, were inspired by Charleton’s harmonisation of theories and experimental methods.
Death and legacy
Charleton’s fall from favour was as sudden as his early rise. He descended rapidly into a state of depression and isolation after 1691. Estranged from his former friends and learned society, he may have felt that he had failed in his aim ‘to erect an intire Fabrick of Physicall Science – as to the Solution of all Natures Phenomena’. However, the echoes of his legacy were eventually felt in the harmonised study of the physical and chemical properties of the natural world, as well as in the experimental methods he espoused.