René Descartes (1596-1650) is best known now for his contributions to Philosophy, which were perhaps the most significant advances in philosophical thinking since the works of Plato and Aristotle over a thousand years prior, and which set the agenda for European philosophical thought even through to the modern day. He famously argued that we ought to secure a foundation to knowledge by asking what we can doubt, and concluded that we can doubt everything, except that ‘I think, therefore I am’: the fact that I doubt means that I exist. This is the only utterly indubitable fact for the person who follows Descartes’ method of doubt.

In his time, however, Descartes was known as a Natural Philosopher, a precursor to a modern ‘scientist’, before the study of the natural world was regarded as different from and separate to philosophy. His work ranged across what we now call philosophy, mathematics, physics, and physiology. He was a proponent of the then-popular mechanical world-view, and his mechanical physical theories influenced, and competed with, Isaac Newton’s.

The Whipple Library has several copies of significant texts by Descartes, some of them with interesting and exciting provenance. Robert Whipple owned several books by Descartes, including an edition of his Meditationes de prima philosophia (‘Meditations on first philosophy’) printed in 1663 (STORE 22:25). There is also a 1953 edition of Discours de la method (‘Discourse on the Method’) in the Buchdal Collection (STORE BUCHDAL 226), owned by the first head of the History and Philosophy of Science department, Gerd Buchdal.

Perhaps most excitingly, there are several copies of books by Descartes that were owned by James Clerk Maxwell in the library’s collection, including a white vellum-bound printing of Principia philosophiae (‘Principles of Philosophy’)  from 1650, the year that Descartes died (STORE 72:5). Maxwell worked down the road from the Department of History and Philosophy of Science (then the Laboratory of Physical Chemistry) at the then Cavendish Laboratory, where he was the university’s first Cavendish Professor of Physics. His contributions to physics, particularly in the full unification of electricity and magnetism into electromagnetism, were among the most significant since Newton, and paved the way for the new 20th century physics of relativity and quantum mechanics. Books from his library were bequeathed first to the Cavendish Laboratory’s library by his widow, Katherine Clerk Maxwell, and then to the Whipple Library for reasons that are unfortunately now unknown to us (although we can speculate that it may have been when the Cavendish Laboratory moved to its present location in West Cambridge).

Descartes is a thinker who sits at the nexus of the history of science and philosophy, a natural philosopher who saw the study of knowledge and the study of the world as continuous rather than distinct, and the editions of his works in the Whipple draw together the history of science, the history of physics, and philosophy, as well as the history of the University of Cambridge itself.