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Thank you. Welcome to Rationally Speaking, the podcast where we explore the borderlands between reason and nonsense.

I'm your host, Julia Galef, and I'm here with today's guest, Stephen Webb.

Stephen is a physicist. He's at the University of Portsmouth, and he's the author of several

books on cosmology, science fiction, and other topics, including Where Is Everybody?

75 solutions to the Fermi paradox and the problem of extraterrestrial life. That's what we're

going to talk about today. Stephen, welcome to rationally speaking. Hi, Julia, and thank you for inviting me.

So I just want to say one of the many things that I really appreciated about your book is this structure

of laying out a taxonomy of different approaches or solutions or I just wish that

more books out there presented taxonomies. I just find it incredibly instructive to have,

you know, this juxtaposition of different ways that people have thought about a problem.

And even sort of the basic structure of that list, the basic categories that

you grouped those solutions into was super helpful in organizing my thinking. So I don't want

...