Credits

A walnut looks like a brain, and therefore could cure brain diseases — in pharmaceutical science and natural remedies today, a traditional medicinal idea ‘doctrine of signatures’ is often cited, as a belief that plants’ morphological resemblance to human organs indicate their curative effects. While this doctrine was often described as an ancient, traditional and even pre-historical idea, it was only first conceptualised as a full-blown theory by Swiss physician Paracelsus and gained its name, the ‘doctrine of signatures’,through early modern medical debates. Today, the doctrine of signatures has been frequently mentioned as a medical philosophy, an emblematic world view or allegorical reading of nature; yet it has not been systematically examined in early modern therapeutic practices, from chymical laboratories to household recipes. Meanwhile, despite being famously rejected by some influential scientists such as John Ray, this doctrine’s persistent influence on late seventeenth-century botanical and medical sciences has often been undermined.

This project aims to penetrate layers of myths concerning the doctrine of signatures, and historicise this doctrine in practices of early modern alchemy, medicine and natural history. It primarily focuses on German- speaking areas and England in the sixteenth and seventeenth century, while taking the broader temporal and geographical scale into consideration. It will challenge the treatment of this doctrine as a monolithic cosmology, and instead approach it as a fluid, malleable set of ideas and practices developed and transformed throughout the time.