> When we decide whether certain mathematical claims are true or not, say, Fermat's last theorem---we prove them mathematically, we don't want to appeal to their utility or lack thereof, right?
Well, sort of. We don't care about the utility of Fermat's last theorem per se, but the only reason we care about numbers, which is what Fermat's last theorem is about, is because numbers have utility. It turns out that, having invented numbers for their utility, they also make fun mental playthings. But they were invented to keep track of how many sheep you had.
> Well, truth is a thing regardless of whether or not we evolved to be able to hold such a concept in our minds, no?
No. Truth is a property of propositions, so it only makes sense to talk about truth in the context of something that can harbor a proposition. If such a thing does not exist then neither do propositions and hence neither does truth. It's kind of like talking about "the mass of an idea". Mass is a property of matter, so it doesn't make sense to apply it to something that isn't made of matter.
The thing that encodes propositions doesn't have to be a human brain, of course. It could be an alien brain, or a computer, perhaps even a thermostat (that one is debatable). But it has to be something.
Well, sort of. We don't care about the utility of Fermat's last theorem per se, but the only reason we care about numbers, which is what Fermat's last theorem is about, is because numbers have utility. It turns out that, having invented numbers for their utility, they also make fun mental playthings. But they were invented to keep track of how many sheep you had.
> Well, truth is a thing regardless of whether or not we evolved to be able to hold such a concept in our minds, no?
No. Truth is a property of propositions, so it only makes sense to talk about truth in the context of something that can harbor a proposition. If such a thing does not exist then neither do propositions and hence neither does truth. It's kind of like talking about "the mass of an idea". Mass is a property of matter, so it doesn't make sense to apply it to something that isn't made of matter.
The thing that encodes propositions doesn't have to be a human brain, of course. It could be an alien brain, or a computer, perhaps even a thermostat (that one is debatable). But it has to be something.