Point taken, but if the only oceangoing thing we’ve ever encountered or, in any real detail imagined, is this old rotten canoe, one might be excused for finding the notion that ‘this canoe is not seaworthy’ a little strange. At that point, we don’t even have reason to think that seaworthyness admits of variation, nor do we have any way of disentangling the capacities of this canoe from properties of the ocean.
Though perhaps I’ve gotten this backwards. Maybe ‘the brain is not trustworthy’ is intended to be metaphorical language.
I’m sorry, I was speaking elliptically. I meant that your canoe metaphor is misleading, because you’re suggesting a world in which the only seagoing vessel I know of is this canoe, while at the same time trading on my actual knowledge of much more seaworthy vessels. This is a problem, given that my whole point is ‘what meaning can a term like ‘trustworthyness’ have if we deny generally to the only thing capable of being trustworthy?′
But I think I’ve decided to take Neotenic, and EY’s comment as a metaphor, so I drop my objection.
By “trustworthiness” I understand something like probability of error, or accuracy or results, just as “seaworthiness” refers to capability of surviving trips of given difficulty. These properties don’t depend on availability of better tools, and so absence of better tools is not a relevant consideration in deciding the state of these properties. The absence of better tools might mislead one to overestimate the quality of available tools, but now that we’ve noticed that, let’s stop being misled.
These properties don’t depend on availability of better tools
The properties themselves do not, but that’s not the problem. Our ability to identify errors in our reasoning hangs on our ability to get that very reasoning right at some point. And getting it right some of the time isn’t enough; we have to know that we got it right in order to know that we previously made an error. Since all we have are brains, we can only say that brains are untrustworthy if some other brains, or the same brain at some other time, are trustworthy (not just correct).
What I mean is that the idea of ‘trustworthyness’ only has meaning in the sentence ‘brains in general are untrustworthy’ if that sentence is false. Some brains must be trustworthy some of the time, or else we’d never know the difference. EDIT: And in fact everything we know about trustworthyness, we learned from trustworthy brains.
We can of course wish that brains in general were more trustworthy than they are and that’s what I take the original comment to mean.
Good point, though it remains that in order to identify 1=2 as an error, we have to be trustworthy in some respect. But you’re right that we don’t have to get that very bit of reasoning right just to know that we got it wrong.
If we have nothing more seaworthy than an old rotten canoe, the canoe doesn’t thereby become a safe means of sailing.
Point taken, but if the only oceangoing thing we’ve ever encountered or, in any real detail imagined, is this old rotten canoe, one might be excused for finding the notion that ‘this canoe is not seaworthy’ a little strange. At that point, we don’t even have reason to think that seaworthyness admits of variation, nor do we have any way of disentangling the capacities of this canoe from properties of the ocean.
Though perhaps I’ve gotten this backwards. Maybe ‘the brain is not trustworthy’ is intended to be metaphorical language.
This doesn’t seem like a relevant concern.
I’m sorry, I was speaking elliptically. I meant that your canoe metaphor is misleading, because you’re suggesting a world in which the only seagoing vessel I know of is this canoe, while at the same time trading on my actual knowledge of much more seaworthy vessels. This is a problem, given that my whole point is ‘what meaning can a term like ‘trustworthyness’ have if we deny generally to the only thing capable of being trustworthy?′
But I think I’ve decided to take Neotenic, and EY’s comment as a metaphor, so I drop my objection.
By “trustworthiness” I understand something like probability of error, or accuracy or results, just as “seaworthiness” refers to capability of surviving trips of given difficulty. These properties don’t depend on availability of better tools, and so absence of better tools is not a relevant consideration in deciding the state of these properties. The absence of better tools might mislead one to overestimate the quality of available tools, but now that we’ve noticed that, let’s stop being misled.
The properties themselves do not, but that’s not the problem. Our ability to identify errors in our reasoning hangs on our ability to get that very reasoning right at some point. And getting it right some of the time isn’t enough; we have to know that we got it right in order to know that we previously made an error. Since all we have are brains, we can only say that brains are untrustworthy if some other brains, or the same brain at some other time, are trustworthy (not just correct).
What I mean is that the idea of ‘trustworthyness’ only has meaning in the sentence ‘brains in general are untrustworthy’ if that sentence is false. Some brains must be trustworthy some of the time, or else we’d never know the difference. EDIT: And in fact everything we know about trustworthyness, we learned from trustworthy brains.
We can of course wish that brains in general were more trustworthy than they are and that’s what I take the original comment to mean.
Careful with “identify” there. If I come up with a proof that 1=2, I can recognize it’s not right without thereby also knowing which step is wrong.
Good point, though it remains that in order to identify 1=2 as an error, we have to be trustworthy in some respect. But you’re right that we don’t have to get that very bit of reasoning right just to know that we got it wrong.