You can have some fun with people whose anticipations get out of sync with what they believe they believe.
I was once at a dinner party, trying to explain to a man what I did for a living, when he said: "I don't believe Artificial Intelligence is possible because only God can make a soul."
At this point I must have been divinely inspired, because I instantly responded: "You mean if I can make an Artificial Intelligence, it proves your religion is false?"
He said, "What?"
I said, "Well, if your religion predicts that I can't possibly make an Artificial Intelligence, then, if I make an Artificial Intelligence, it means your religion is false. Either your religion allows that it might be possible for me to build an AI; or, if I build an AI, that disproves your religion."
There was a pause, as the one realized he had just made his hypothesis vulnerable to falsification, and then he said, "Well, I didn't mean that you couldn't make an intelligence, just that it couldn't be emotional in the same way we are."
I said, "So if I make an Artificial Intelligence that, without being deliberately preprogrammed with any sort of script, starts talking about an emotional life that sounds like ours, that means your religion is wrong."
He said, "Well, um, I guess we may have to agree to disagree on this."
I said: "No, we can't, actually. There's a theorem of rationality called Aumann's Agreement Theorem which shows that no two rationalists can agree to disagree. If two people disagree with each other, at least one of them must be doing something wrong."
We went back and forth on this briefly. Finally, he said, "Well, I guess I was really trying to say that I don't think you can make something eternal."
I said, "Well, I don't think so either! I'm glad we were able to reach agreement on this, as Aumann's Agreement Theorem requires." I stretched out my hand, and he shook it, and then he wandered away.
A woman who had stood nearby, listening to the conversation, said to me gravely, "That was beautiful."
"Thank you very much," I said.
Part of the sequence Mysterious Answers to Mysterious Questions
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A few questions and comments:
1) What kind of dinner party was this? It's great to expose non-rigorous beliefs, but was that the right place to show off your superiority? It seems you came off as having some inferiority complex, though obviously I wasn't there. I know that if I'm at a party (of most types), for example, my first goal ain't exactly to win philosophical arguments ...
2) Why did you have to involve Aumann's theorem? You caught him in a contradiction. The question of whether people can agree to disagree, at least it seems to me, is an unnecessary distraction. And for all he knows, you could just be making that up to intimidate him. And Aumann's Theorem certainly doesn't imply that, at any given moment, rectifying that particularly inconsistency is an optimal use of someone's time.
3) It seems what he was really trying to say was someting along the lines of "while you could make an intelligence, its emotions would not be real the way humans' are". ("Submarines aren't really swimming.") I probably would have at least attempted to verify if that's what he meant rather latching onto the most ridiculous meaning I could find.
4) I've had the same experience with people who fervently hold beliefs but don't consider tests that could falsify them. In my case, it's usually with people who insist that the true rate of inflation in the US is ~12%, all the time. I always ask, "so what basket of commodity futures can I buy that consistently makes 12% nominal?"
To point 4 and inflation, the trick is to not invest in commodity futures (where the deflationary pressures of improved production technology cancel some of the inflationary pressures of currency devaluation) but rather assets. You can invest in the S&P 500 and achieve ~11% nominal returns. Now whether asset prices are relevant to "inflation" is dependent upon whether you are trying to answer the question of "how many apples could I buy for a dollar in 1960 versus today?" or the question "how many apples could I buy for a dollar today if they were produced with the same inputs and technological process as they were in 1960?"