Hello everyone, welcome to the Binescape Podcast. I'm your host Sean Carroll. In various

conversations, both here on the podcast and elsewhere, out there in what you might think

of as the real world, I've noticed that the topic of extraterrestrial life, life on

other planets elsewhere, let's just say in our galaxy, is one that engenders very strong

emotional reactions. People feel very strongly about this topic, about whether or not such

life exists, about whether or not it will be technologically advanced, whether it will be

friendly, whether it will be like us or something completely different. Which when you think

about it is funny. I mean, why should you have such emotional reactions about something,

about which we know so little, about which there is so little data. I think that it's

okay. I mean, as a good Bayesian, you're going to have priors about the likelihood of certain

things, but you shouldn't be so confident one way or the other. I have my own beliefs. You

know, I think that it's actually unlikely that in our galaxy, there are other very advanced

technological civilizations out there. If I didn't know anything, if I didn't have any

data at all, I would think that might be very likely. There are a lot of planets out there

after all. But if there were technologically advanced civilizations, it would be very

easy to have noticed them already. And we haven't. Now, maybe they're hiding or whatever

perfectly possible, but it's just easiest to imagine they're just not there. But again,

we should be open minded. I could be completely wrong about this. When it comes to what life

is going to be like, again, we know very little, it's certainly very plausible that life

is ubiquitous, but it's just single-celled or extremely primitive in all sorts of ways.

If life does become complicated, if you get eukaryotic or the equivalent multicellular

life in a variety of different configurations, what are those organisms going to be like?

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