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Welcome to rationally speaking, the podcast where we explore the borderlands between reason and nonsense.

I'm your host, Julia Galef, and my guest today is David Mannheim.

David is a decision theorist with a PhD in public policy from Party Rand Graduate School.

And one of the topics that David has studied and written a lot about over the years and blog posts and academic articles alike is a principle called Goodhart's

Law, which is one of those, it's in that small set of deceptively simple principles that

once you understand it, it kind of explains so

much of what's wrong with the world. So Good Hearts Law, you might have heard it stated as

when a measure becomes a target, it ceases to be a good measure. So we're going to talk today

about what that means how Good Heart's Law shows up and kind of the dynamics of how it

works. So, David, welcome to rationally speaking. Thanks. I'm excited to be here. I'm curious how

you got interested in Goodhart's Law in the first place, and specifically whether it was more

like seeing how consequential this law is to education and healthcare and policy and business and things like that in the real world versus the kind of mathematicians.

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