The Economist reports from this year’s AAAS meeting about a fascinating lecture delivered by the historian of science Lawrence Principe about his quest to figure out the real history of alchemy. Principe has done some impressive work to brush away the Whig history of modern chemistry and understand alchemy on its own terms.
Alchemy is saddled with such a bad reputation that many people don’t appreciate how it played an important role in the birth of modern sciences, such as biochemistry and neurology.
Here’s part of a blog post I wrote in 2006 on this surprising link:
Jan Baptist van Helmont, a sixteenth-century Belgian alchemist, carried out a classic experiment on biological growth. He put a five pound willow sapling in a tube of 200 pounds of earth. For five years he gave the tree nothing but water, and then weighed both tree and earth. The tree had grown to 169 pounds, while the earth had lost a few ounces. “Hence one hundred and sixty-four pounds of wood, bark, and roots have come up from water alone,” he announced. Van Helmont believed that the willow was nothing more than transmuted water, given form by the willow’s inner soul.
I first came to appreciate the importance of alchemy in the rise of biochemistry while working on my book Soul Made Flesh, on the history of neurology. Thomas Willis, the first neurologist, started out as an alchemist, deeply influenced by Van Helmont. He came into contact with Robert Boyle through their shared interest in alchemy. And his first important work was a book that used alchemy to reinterpret physiology. Instead of the four humours, Willis saw body being made up of corpuscles of different sorts, borrowing concepts of Van Helmont and other alchemists. These corpuscles interacted with one another to produce changes, just as ferments made bread rise and grape juice turn to wine.
Willis later did groundbreaking work on the anatomy and function of the brain, which until his time had generally been considered a pretty useless organ. Willis envisioned the brain as an alembic, the distilling container of alchemy, in which some of the corpuscles of the blood were distilled into the animal spirits, which then flowed through the nerves. While some of Willis’s language and concepts are now hopelessly old-fashioned, he set the study of the brain — and thus the soul — on a new foundation.
The intersection of alchemy and biology is just further evidence that science does not advance by simply wiping the slate clean and starting completely from scratch. Some of the most dramatic revolutions were born within systems of thought that today seem hopelessly backwards. I wonder how twenty-ninth cenutry historians will look back at our own revolutions today. Who will be cast aside as the new alchemists?
Originally published February 24, 2011. Copyright 2011 Carl Zimmer.