Theories and laws – what is science anyway? (part 3)

(Einstein was a patent clerk)

So on one hand science is observing the world around us, coming up with explanations and putting them to the test. It’s also a body of knowledge, however, composed of theories and laws that help us understand how the universe works.

Famous scientists like Newton, Darwin and Einstein are famous not so much for the experiments they did than for the.amazing theories and laws they came up with.

Of course, we’re all philosophers – after a few drinks who doesn’t have a theory about how the world works?

But in science, the word ‘theory’ means a thorough explanation that makes sense of the gathered evidence. A law  can be used to predict what will happen.

So for example:

Newton was the first to come up with maths that explained how gravity worked.

Darwin worked out how life evolves.

Einstein changed how we understand space and time.

These were amazing thinkers. But they weren’t unique. Science isn’t the story of maverick prophets who come up with the answers all by themselves. Usually breakthroughs happen as a result of the work of many scientists over time. Newton himself said:

If I have seen further it is by standing on the shoulders of Giants.’

By which he meant that he couldn’t have done the work he did if it wasn’t for great scientists who came before him.

But science is a book to which each generation adds new pages. Mainstream scientific theories are constantly being examined and improved.

Newton’s theory of gravity was shown to be incomplete by Einstein’s work.

Darwin didn’t know that genes existed.

Einstein’s theories of relativity are challenged all the time – so far they’re holding up well but that doesn’t stop scientists from trying. They’d become famous if they did!

How can we trust science if the answers it gives keep changing?

I was once at a festival and heard someone complain: ‘Science says one thing today and another tomorrow – why should we trust them?’

Scientists do sometimes change their mind about how the world works. That’s their superpower, remember? And it’s a good thing. Only fanatics never change their minds.

But it’s not that scientists decide that the moon is a rock one day and a ball of cheese the next.

Rather it’s that our understanding gets deeper and more nuanced with time. We also get better at measuring stuff and find more stuff to measure.

Imagine you see something in the distance. You think maybe it’s a tree. But no, it’s getting bigger, it must be moving and trees don’t do that – maybe it’s a car? But it’s getting closer and you can’t hear an engine, in fact it looks like an animal of some kind, perhaps a horse? The ground starts to shake and you see now it has horns and you’re pretty sure horses don’t have those…what is that, is it maybe a moose? Maybe you shouldn’t be standing still while it’s charging towards you?

It’s not that you were wrong each time so much as you came up with the best explanation you could with the information you had. If you had binoculars you might have known enough to start running away earlier…


Further reading: – a more in-depth look at what a scientific theory is – some of the groundbreaking theories in the history of science