So I agree that this move of bringing up assumptions isn’t necessarily a conversation halter. But if it just comes down to people having different notions of what is self-evident… well then it is a conversation halter. That is why I don’t think a discussion about our assumptions should be about their self-evidence. Here are some other features of assumptions that can be used to evaluate them: utility, parsimony, generality, predictive capacity, fruitfulness.
Assuming the existence of a God has no utility, negative parsimony, zero predictive capacity and while fruitful in some circumstances, extremely destructive in others. Assuming induction as valid on the other hand...
ETA: Also, a lot of time all the assumptions an empiricist or physicalist needs are already implicit in the discourse. You can bootstrap from there.
Or take propositional logic. Assume A=A. Or don’t. But if you don’t your logic is useless.
OK, it might likely be a conversation halter, but maybe it should be. If your view is being attacked based on initial assumptions you don’t agree with, you can just state that. In this case, you might have good reason to cut off the flow of debate.
But even if you don’t want to halt the conversation, if visiting initial assumptions is the next step, what else can you do?
I’m all about visiting initial assumptions. But declaring your assumptions “self-evident” isn’t a justifying move. All this means is “I don’t have any reasons for believing it, but I do.” Now if there were no ways around that it wouldn’t be a silly thing to say. But look! There are ways to talk about propositions even when we have to stop talking about whether those propositions correspond to reality! So now we don’t have to stop talking. More than that, it doesn’t make sense to stop talking because “My assumptions are useful, fruitful, and parsimonious and yours are not.” is close to a knock out response to “I have no reason to believe this, but I do.”
My impression is that the conversation ends because at least one side isn’t willing to argue about initial assumptions. (Indeed, if there was an argument for it, it wouldn’t be an assumption.) People will just say things like, ‘it is self-evident that ….’ or, ‘oh, if you don’t even believe that then there’s nothing to talk about!’.
I was presenting this as an example of a discussion failure mode. I don’t suppose that it is necessary. But I also hadn’t known about those other ways of arguing about initial assumptions—utility, parsimony, etc. Those sound like very productive places to begin.
So we agree it’s not a conversation halter unless one person won’t proceed past, ‘my assumptions are self-evident!’.
So we agree it’s not a conversation halter unless one person won’t proceed past, ‘my assumptions are self-evident!’.
I think you’re missing the other kind of conversation halter here: the person might not even claim their assumptions are self-evident, but simply say that they’re axioms and not subject to further analysis. This is the conversation halter RobinZ has been describing.
Agreement! Good for us. So then a question for the rest of the thread: is “appeal to inescapable assumptions” the same things as “appeal to self-evidence”? If so then it looks like we all agree but perhaps Eliezer didn’t phrase the example well.
So I agree that this move of bringing up assumptions isn’t necessarily a conversation halter. But if it just comes down to people having different notions of what is self-evident… well then it is a conversation halter. That is why I don’t think a discussion about our assumptions should be about their self-evidence. Here are some other features of assumptions that can be used to evaluate them: utility, parsimony, generality, predictive capacity, fruitfulness.
Assuming the existence of a God has no utility, negative parsimony, zero predictive capacity and while fruitful in some circumstances, extremely destructive in others. Assuming induction as valid on the other hand...
ETA: Also, a lot of time all the assumptions an empiricist or physicalist needs are already implicit in the discourse. You can bootstrap from there.
Or take propositional logic. Assume A=A. Or don’t. But if you don’t your logic is useless.
OK, it might likely be a conversation halter, but maybe it should be. If your view is being attacked based on initial assumptions you don’t agree with, you can just state that. In this case, you might have good reason to cut off the flow of debate.
But even if you don’t want to halt the conversation, if visiting initial assumptions is the next step, what else can you do?
I’m all about visiting initial assumptions. But declaring your assumptions “self-evident” isn’t a justifying move. All this means is “I don’t have any reasons for believing it, but I do.” Now if there were no ways around that it wouldn’t be a silly thing to say. But look! There are ways to talk about propositions even when we have to stop talking about whether those propositions correspond to reality! So now we don’t have to stop talking. More than that, it doesn’t make sense to stop talking because “My assumptions are useful, fruitful, and parsimonious and yours are not.” is close to a knock out response to “I have no reason to believe this, but I do.”
A few comments above I wrote,
I was presenting this as an example of a discussion failure mode. I don’t suppose that it is necessary. But I also hadn’t known about those other ways of arguing about initial assumptions—utility, parsimony, etc. Those sound like very productive places to begin.
So we agree it’s not a conversation halter unless one person won’t proceed past, ‘my assumptions are self-evident!’.
I think you’re missing the other kind of conversation halter here: the person might not even claim their assumptions are self-evident, but simply say that they’re axioms and not subject to further analysis. This is the conversation halter RobinZ has been describing.
Agreement! Good for us. So then a question for the rest of the thread: is “appeal to inescapable assumptions” the same things as “appeal to self-evidence”? If so then it looks like we all agree but perhaps Eliezer didn’t phrase the example well.