Age of Invention: Knowledge Lost and Found

One of the durable shapes of modern thought is to assume that pre-scientific knowledge was uniformly bad, that our ancestors were credulous fools whose remedies harmed more than they helped, and that everything good in medicine arrived after Pasteur. Howes's piece is interesting because it pushes back on this comfortable story with specific cases. The piece arrives at a useful moment in a culture that has only recently rediscovered how much practitioners can know without being able to explain why.nnThe central claim is that bad theories often produced workable practices through the back door. Mercury for syphilis was prescribed for centuries on entirely mistaken theoretical grounds, yet it appears to have worked in roughly the same way modern chemotherapy works — by being toxic enough to kill the bacterium before killing the patient. In the 1880s mercury was replaced by bismuth salts (still toxic to the pathogen, less toxic to humans), and in the early 20th century by Salvarsan and Neosalvarsan (arsenic compounds, less unpleasant still). The pattern across the four-century arc was less "useless folly replaced by science" than "a careful sequence of poison choices, each one slightly less brutal."nnThe second hinge is the Lazaretto example, which arrived centuries before germ theory. Mediterranean cities had already built dedicated quarantine islands for arrivals from plague-ridden ports — using miasma theory's wrong premise to land on broadly the right practice. The terra sigillata clay from Lemnos, used for over two thousand years as a cure-all, may have worked at least partly because its bentonite-like composition genuinely absorbed certain toxins and pathogens. Knowing why something works and getting it to work are not the same accomplishment.nnWe picked this because Howes's running project — taking pre-modern competence seriously — is one of the more clarifying threads in current history writing. Useful for anyone tired of the Whiggish story of progress. The harder question to sit with is which of our own working practices we cannot yet explain.