Materialism and ‘the soft substance of the brain’: Diderot and plasticity

Abstract

ABSTRACTMaterialism is the view that everything that is real is material or is the product of material processes. It tends to take either a ‘cosmological’ form, as a claim about the ultimate nature of the world, or a more specific ‘psychological’ form, detailing how mental processes are brain processes. I focus on the second, psychological or cerebral form of materialism. In the mid-to-late eighteenth century, the French materialist philosopher Denis Diderot was one of the first to notice that any self-respecting materialist had to address the question of the status and functional role of the brain, and its relation to our mental life. After this the topic grew stale, with knee-jerk reiterations of ‘psychophysical identity’ in the nineteenth-century, and equally rigid assertions of anti-materialism. In 1960s philosophy of mind, brain–mind materialism reemerged as ‘identity theory’, focusing on the identity between mental processes and cerebral processes. In contrast, Diderot’s cerebral materialism allows for a more culturally sedimented sense of the brain, which he described in his late Elements of Physiology as a ‘book – except it is a book which reads itself’. Diderot thus provides a lesson for materialism as it reflects on the status of the brain, science and culture.