I have been listening, for my own amusement, to a history of chemistry as audiobook. It wasn’t a history when it was written – it was intended to be a non-technical take on what chemistry could do for mankind to inspire and reduce the fears of the time that surrounded the science. It’s a fascinating take on not only the progress we’ve made in the field, but also the culture of the time. Listening to it leads to me suppressing a giggle at work fairly often – not because it’s intended to be funny, but it is.
Yesterday I got to the chapter on the Adulteration of Foods. You can find it here – and it’s less than 15 minutes long, so it’s not like you need to listen to the whole book. Some of it was mildly interesting – who knew that counterfeiting milk was such a big deal? – but what really struck me was the almost offhand mention of the addition of formaldehyde to milk. Not as an adulterant, no, as a preservative. Now, most of my readers are probably familiar with the concept that formaldehyde is a preservative, but most of us also know that it’s carcinogenic (and not just in California) as well as… well, it’s just nasty. I can’t imagine drinking milk with formaldehyde in it. There was brief mention in the article about concern over children drinking the most milk, and their consumption of larger amounts than adults… but that was all.
We have, looking back into history, often started out doing something that later we discovered was exactly the wrong thing to do, and it ended in disaster. The science of the moment supported what was believed to be the best practice… but then questions cropped up and science took a closer look and we no longer have formaldehyde in our milk. The problem comes when questions are asked, and the answer given is ‘the science is settled.’
That’s just nonsense. By it’s very nature science is a constant inquisition. Scientists who no longer answer – or ask – questions have reached the senescence of their usefulness. There are a few ways to look at the world around us. There’s what we know. There’s what we don’t know. But what if what we know isn’t so? And what if we do know more about the unknown, through the use of theory, than we at first realize? I’ll explain. Most of us grew up thinking that a theory was a guess, at best. ‘I have a theory that the teacher will give us pop quizzes every Friday’ and then wait to see what happens.
The word has more than one meaning, and in science, theory does not mean what most people think that it means. The Merriam-Webster breaks the word down into six definitions, but I’ll look at two (one of which is lumped together). One is the meaning most of us apply to it – that it is conjecture, or speculation, based on abstract thought “a hypothesis assumed for the sake of argument or investigation : an unproved assumption.”
When someone hears, then, ‘the theory of gravity’ they might assume that there is some wiggle room in it. It’s something that isn’t fully thought-out and if you go up to the tenth floor and jump out, you might not expect the inevitable to happen. Right. You just go right ahead with your theory, buddy… What scientists mean when they say ‘theory’ is a little different than the student trying to get one up on his teacher. So “a plausible or scientifically acceptable general principle or body of principles offered to explain phenomena” is what we are invoking with our theory of gravity. No, it’s not a law of nature, only because by it’s nature we cannot set proofs up. But we can ask questions, observe, and gather data. All of that tells us that if you jump off the tenth floor, you’re going to be messed up at the bottom and unlikely to be able to prove your hypothesis. Which is another word that isn’t commonly understood.
Science has theories, and makes hypotheses carefully, with precise phrasing. Taken lightly, that phrase might indicate that science is blinking in the dark, and sometimes it sure feels like that. It’s dark, it’s dark, it’s dark… there’s a flash of light. But if you blink long enough, eventually you can piece together a picture of the world around you from those glimpses of stars, and even more from the big easy illumination of the moon. After a while, you have a map of the world you’re pretty confident in. But it’s not a perfectly formed map. Yes, there’s a tree there, and don’t walk over that cliff over there. But you might not be able to tell, say, what the composition of the soil is. Or, to name a developing field of understanding in science, what microbes are in the soil and how they are interacting with the plants growing in that soil. You can use that imperfect map to guide your questions more and more accurately, anticipating the answers before you get them. What you cannot do is to ignore the asking questions, and testing answers, part. If you start to assume you know everything that you can know about an area, you’re going to fall into a crevasse and later generations will look at your frozen remains and cluck their tongues over the poor lost traveler.
We used to put formaldehyde in milk and then hand it to children. We used to think that low-fat, high-carb was the healthy way to eat. We think that faster-than-light travel is impossible. We’ve asked questions, and painfully drawn answers from blinking in the dark with instruments that would make today’s students flinch. Or no instruments at all, until some bright spark like Leeuwenhoek came along. When we’ve gotten answers, we’ve let others ask those same questions and find out if they could replicate our results. And if they couldn’t, we got to work to find out why. That’s the beauty of science. It never settles into a heap and makes itself comfortable before closing it’s eyes to sit in the dark.