There's a big cloning factory building with a million identical rooms in it. You go into room 1 and are put to sleep and a random number 1-1000 is generated. If it comes up 2-1000, then no clones are made and you're just woken up. If it comes up 1 then an identical copy/clone of you is made in the other 999,999 rooms and all one million of you are woken up at the same time in the same way. You wake up and don't know if you are a clone or the original. What is your credence that the random number generator came up 1 and that clones were made?
This type of problem is debated, of course. I admit that I either never really pursued it or didn’t since 1995 or so, and don’t recall.
But I think that people who count wake thought instances instead of wake scenario weighted instances seem to be forgetting to distribute the weight in the second case across all the thought-havers.
I’m in the 1 in 1000 odds [I am a clone] camp.
But maybe I’m not being careful enough.
Let’s adjust this scenario so that in the clone situation, 999,999 times out of 1,000,000 all clones would be killed before waking up.
Now it gets confusing for me. There’s a one in 1000 chance I was cloned. And there is a one in 1m chance that 1 million clones are waking up. The odds of the clones awake scenario are tiny. But almost all awake thoughts are had by clones.
Anyone who utters “I am a clone“ will be correct 1 million out of 1,000,001 times if the odds of the scenarios were equal. As posed I need to weight by 1000x because that’s how rare cloning is. But 1000/1,000,000 is a rounding error of a tenth of a percent. So that suggests I should put nearly all my credence in the clone theory.
On the other hand, by my reasoning at the beginning of my comment, the odds that I am not a clone (because I am in the not a clone possible world) are 999 out of 1000.
Yeah, that still seems right to me. Thought instances don’t add up because they aren’t causally independent.
So what of the previous point that suggested putting my credence in being a clone? I failed to take into account that I am not counting the odds I am one of those people but rather the odds that my utterance is taking place in that possible world. The number of duplicate utterances isn’t material, because they aren’t independent. And the odds that I am in a clone world are 1 in 1000.
The confusion comes from the linguistic misdirection of stating that as the odds “I am a clone”. The reason that doesn’t work is a failure to have univocal “I”. In the clone case the I is all of us added up. Not that we are one person. But it’s a linguistic confusion caused by in the usual case “I” always indicates a unique instance of a thought (person and thoughts are 1:1 instead of 1,000,000:1). That is, in the clone case a thought instance isn’t a count of person-instances.
So we normally don’t distinguish between quantifying over worlds and quantifying over thought instances understood as metonymy for the self. But that is a contrivance that isn’t applicable in the clone example