Fifteen hundred years ago everybody knew the Earth was the center of the universe. Five hundred years ago, everybody knew the Earth was flat, and fifteen minutes ago, you knew that humans were alone on this planet. Imagine what you’ll know tomorrow.
– Men in Black
In the film, Tommy Lee Jones’ Kay wants to make Will Smith’s Jay consider what else he might be wrong about (beyond the existence of aliens). In doing so, Kay reinforces two related ideas: knowledge only ever accumulates, and by extension those who came before us were universally more ignorant. Neither one of those is entirely true (nor is it true that 500 years ago the Earth was widely considered to be flat). Knowledge can be lost. A popular example is concrete; we still have not definitively answered the question of how Roman concrete lasted so much longer than our modern attempts. The original recipes for Damascus steel and Greek fire are also gone even if we may have good hypotheses for what they might have been, and we apparently forgot how to prevent scurvy multiple times. Now, when contemporary antibiotics are losing their utility due increasing resistance, we are rediscovering effective antibacterial treatments from our medieval ancestors.
On a recent episode of the podcast Meet the Microbiologist, I was introduced to the work of Steve Diggle and Freya Harrison. Among other work, they are involved in an interdisciplinary research project with medievalists in the arts and humanities to recreate and explore the medical properties of treatments from medieval medical texts. Their first success came with Bald’s eyesalve, a mixture of alliums, wine and oxgall aged in brass and used to treat eye infections. It is effective at killing S. aureus and has completed a Phase I clinical trial. Their latest investigation involves a honey and vinegar, each of which is used individually for therapeutic purposes but no longer in combination.
Obviously I found this interesting simply for the relevance to public health and microbiology. I also appreciated the intent to take older knowledge seriously. Sure, it is possible that some of those therapies were propped up by a combination of superstition and the placebo effect. But our forebears possessed the same cognitive abilities as we do, and the same potential to be pragmatic. They may not have a fully formulated scientific method, but we all have some capacity for working out cause and effect; we have to do a lot of it in our early development. And writing and reproducing books was way more costly than today, so they’d have an incentive to make sure they were preserving useful ideas. Given all that, taking the a priori position that medieval medicine was more than snake oil seems justifiable. If you have a chance to listen to the podcast, also note where they point out that even something like including prayers as part of a recipe could have mechanistic benefits in addition to spiritual ones.
Part of taking that knowledge seriously is considering the possibility that the whole recipe matters. As Harrison, Diggle and their collaborators note, the reductionist tendencies in contemporary science lead us to try to isolate the one active ingredient from a complicated concoction like Bald’s eyesalve. Maybe it is really just something in the garlic (one of the alliums) or the the alcohol in the wine and the rest is just along for the ride. But as their research showed, none of the individual components work as effectively as the entire mixture with all of the processing steps. And somewhere along the way, we separated honey and vinegar to use separately and lost the benefits of using them together. Simple solutions are appealing, but sometimes the complicated and the complex are necessary.
And in a completely different direction, I’m reminded that this medieval knowledge has reached us partly because books turn out to be a pretty good way to transmit information over extended periods of time. The longevity of newer media has already been called into question. Bit rot can undermine the integrity of digital storage, including magnetic tapes and drives and optical disks. Material published online can disappear without notice. I would not be surprised if my print book lasts longer than any of the hundreds of posts I’ve written here. (Imagine my dismay then when I visited the campus bookstore of my alma mater today only to discover that there was not a single book on any of the shelves.)
Now, don’t think for a second that I am waxing nostalgic for the world as it was a thousand years ago. As clumsy as I am, I have no desire to live in a world where a simple nick could prove fatal following a wound infection, not to mention the open sewers and the feudal system and the complete lack of X-Men comics. The old ways weren’t all better. But the good ideas are worth carrying forward. And if we value ideas from the past, we should make sure the good ideas of the present are available to our descendants as the wisdom of their past.
About the author:
Andy has worn many hats in his life. He knows this is a dreadfully clichÃ©d notion, but since it is also literally true he uses it anyway. Among his current metaphorical hats: husband of one wife, father of two teenagers, reader of science fiction and science fact, enthusiast of contemporary symphonic music, and chief science officer. Previous metaphorical hats include: comp bio postdoc, molecular biology grad student, InterVarsity chapter president (that one came with a literal hat), music store clerk, house painter, and mosquito trapper. Among his more unique literal hats: British bobby, captain's hats (of varying levels of authenticity) of several specific vessels, a deerstalker from 221B Baker St, and a railroad engineer's cap. His monthly Science in Review is drawn from his weekly Science Corner posts -- Wednesdays, 8am (Eastern) on the Emerging Scholars Network Blog. His book Faith across the Multiverse is available from Hendrickson.