Letter XIV of Voltaire’s Lettres philosophiques provides an insight into the early days of modern science, contrasting the theories of Descartes and Newton at a time in which Newtonian physics was new and controversial. The vitality of the debate as approached in this volume struck me, as a humanities student, more intensely than GCSE science lessons ever managed to; it made me realise that even the laws of gravity were a new discovery once.However, it was the way in which Descartes’ world was depicted that left a greater mark on me, through its apparent strangeness (although, had I heard about it in a physics classroom, no doubt it would seem as banal as gravity). In Voltaire’s portrayal, the emphasis is on movement, ‘tourbillons de matière subtile’, next to which our modern conception of gravity seems, if more accurate, somehow less dynamic. This theoretical universe is a crowded one, where light ‘existe dans l’air’ and the dominant forces are pushing ones; Newton’s is an elegant void, where movement is due to attraction.
After studying the letter, I wrote the poem below, inspired both by the painterly quality of Voltaire’s images, and the way in which reading it had offered me a new perspective on the way human knowledge changes. Letter XIV typifies a time very different from our era of specialization, where science and the humanities are carefully cordoned off from one another. Voltaire was spreading something that was, at that time, revolutionary, and it seems unlikely nowadays that a literary figure could be so fully involved with the cutting edge of science. I wanted to capture this sense of change, and the related fact that, while these competing explanations for the universe once ranked side by side, one has now been relegated to the status of image, while the other has become (relatively) unquestioned scientific fact.
Descartes thought the sky was made of spirals,
spangled whirlwind scrawls, a tide of starlight,
oily brushstrokes crowding in the midnight,
currents sweeping past the moon. His rival,
a Mr Newton, won; the Lumières jeered,
and though the sciences were an art those days,
the pictures Descartes saw were just a phase,
an early Van Gogh in the wrong career.
– Rowan Lyster
(Poem first published in the ISIS magazine, Oxford)
 All quotes are from Letter XIV, Lettres philosophiques.