For me, science is a process of reducing uncertainty about the world.

So many people have this craving for certainty.

People want simple solutions for very complex problems. And these simple solutions do not exist.

Uncertainty is not a sign of a problem. I think that we should be learning from this,

that uncertainty is just part of the scientific process.

So that's one way of thinking about that uncertainty, is that that information is spread out in ways that it's not in the classical picture.

We know from research on people and their cognition that if there is uncertainty, they don't just say,

oh, no, I have this uncertainty and now I can't act. Your brain, your mind fills in this

uncertainty, but in a smart way. It's like autocorrect. It's like smart guessing.

There's still so much that's not known and not known in a systematic way or in a quantitative way or

in a comprehensive way. And so that's a huge area of uncertainty. That's very exciting.

I'm Christy Ashwanden, and this is the fifth and final episode of Uncertain, a scientific American

podcast. On this show, we've been talking about uncertainty from a variety of angles.

We've heard how uncertainty can be a spark for creativity and scientific discovery. We've discussed

how uncertainty can go unseen and make science really difficult. And we've explored some of the

research techniques and habits of mind that researchers use to deal with uncertainty.

Today we're going to end with two final questions. If science is always uncertain, how can we ever know anything?

How can we have confidence in science if there's always underlying uncertainty?

For help with these questions, I turn to Kevin McCain, Professor of Philosophy at the University of Alabama, Birmingham, and co-author of the book, Uncertainty, How It Makes Science,

My main areas of research are epistemology and philosophy of science.

So epistemology, I work a lot in the nature of evidence kind of in general and what makes

beliefs rational.

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