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Turtle Cakes:


If there is no expertise anymore, I'm not sure there's anything to base true agreement on. People who are chipping away at the idea of objective knowledge are chipping away at the foundation of their own society.

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Preorder John's new book, Turtles All the Way Down, out October 10th 2017! You can find links to both the signed and unsigned editions here: and information on how to (probably) get a signed copy here:
Good morning John.
My life this week has been dictated by natural phenomenon. As Montana has continued through an unseasonably hot and dry summer, my valley has been socked with smoke, sometimes enough that experts advise me not to leave my house - certainly not with an infant, and that got substantially worse when the nearest fire in Lolo National Forest flared and burned more than 9000 acres in one evening. It was beautiful though - I was headed out to get dinner for Katherine and I didn't come home for an hour because I kept stopping to film it, and then of course this Monday there was the eclipse.
One of the remarkable things about the eclipse is that we knew exactly when it was going to happen for decades in advance. We had enough lead time to get a bunch of eclipse glasses made, and septic gas stations all over the country. People booked hotel rooms and braved terrible traffic, though not before first making sure that the sun would be out in the place where they were going. And we trusted all of those things. I couldn't tell you how people figured out when eclipses were gonna show up before computers - but they did it. I also don't know how scientists fight fires, or predict them, or know to tell me when I shouldn't go outside to avoid damaging my lungs, but I do know that someone knows. Someone knows when the eclipse will happen, someone knows when fires will probably get worse, and they've had their work checked by other people who also know. I don't have the space in my head to figure these things out on my own, and, like, 'good thing' because the story of human progress is not a story of every single person figuring out every single thing for themselves.
John, when telling people that I trust experts, I sometimes hear people respond that I'm committing a logical fallacy: appealing to authority. And this is a fallacy when making an argument - saying "but this expert says so" is not a good argument - but I'm not actually making an appeal to one person, I'm making an appeal to a process that has had a good deal of success at accurately explaining and predicting stuff. The expert is the proxy for the process. I'm making an appeal not just to the people who have figured something out, but to all of the other people who I know are gonna check their work. I'm making an appeal to statistics and logic and calculus and peer-review; I'm making an appeal to science. And also I'm often not making an argument: I'm not trying to convince people of what they should believe; I'm trying to explain that when it comes to things that I'm not that interested in or capable of learning enough about, I'm happy to accept scientific consensus because it's going to be a whole lot better than whatever hunch I happen to have. This isn't trusting that they're right; it's accepting that people who study things for a living has a far greater chance of being right than someone who just feels like arguing with them. It's not an appeal to authority - it's like an appeal to sanity.
I get worried about the current tendency of some to feel like they must confirm everything for themselves - that's individualism taken to maybe a fatal extreme. Human progress is a story of building on the work of others, not every single person starting from scratch. I agree that trusting individuals because they've had the expert label applied to them can lead to trouble, but one of the great achievements of our culture, of our society, is the creation and refinement of robust systems for creating and identifying trust-able expertise. Of course, those systems can always be refined and improved, but those who think they can just be discarded scare me. Watching these beautiful and terrible plumes of smoke flare above my town, I felt very grateful to those who study these things for a living so I do not have to.
John, I'll see you on Tuesday.

End screen:
John, happy 40th birthday. Yesterday, we made you a bunch of turtle cakes - I hope that you liked them. There's so many turtle cakes! Also, ROLF, the dumb party game that DFTBA Games is making - its Kickstarter is ending in just a few days, so if you want to help that out and pledge to get a copy there's a link in the description. Also to everybody on the gulf coast of Texas and Louisiana, hopefully it won't be as bad as it looks like it might be, but be safe, make good decisions - thinking about ya.