Science is our way of trying to understand the universe, to make sense of the patterns of objects and behaviours around us and explain the regularity of the world we experience. We use several different words to characterize the ideas and explanations we come up with. A hypothesis is an informed conjecture, a speculation about world which needs to be tested, while a theory is a well-supported, coherent framework which explains some aspect of the universe. Scientific “laws” seem to fall somewhere in between; while they’re very well-supported, they tend to assert things about the world rather than offer an explanation. For example, Newton’s law of gravity enables us to predict the gravitational attraction between two objects but doesn’t explain why objects are attracted to each other.
Most of the laws that people are familiar with probably come from physics or chemistry. What about biology? Does biology have laws? One candidate might be “every species will either speciate or go extinct”. It may seem uninspiring or simplistic, but it’s not that different from Newton’s first law of motion: “objects in motion tend to stay in motion and objects at rest tend to stay at rest unless disturbed by an outside force”. It may not really explain what’s happening, but it does capture a reliable pattern we observe and, at least to me, suggests that something deeper underlies it.
Maybe we should look for an example with more weight, something which is more insightful and not just descriptive. How about “populations of living creatures evolve via natural & sexual selection and/or genetic drift.” That has a bit more depth than the first suggestion; it’s even part of an elaborate theoretical framework involving lots of equations (for those who suffer from math envy). Sure, there’s room for argument — especially about what “living creatures” means — but let’s assume we could agree about the wording: could it be a law of biology? Why or why not?
So here’s my question: Is it possible for there to be “laws of biology”? It’s a pretty big topic, so maybe these prompts will help us get started:
- What do you think “law” means (in the contest of science)?
- Which of my suggestions is a better candidate for a “law of biology”?
- Can you suggest any other potential laws of biology?
- Why is it so much easier to talk about laws of physics?
- What about chemistry? Economics? Anthropology?