I find myself always struggling with these concepts, coming back to this post, kinda-sorta understanding it, but still rather confused. Some questions and comments:
I’ve never heard this before. Where does it come from? Like, the idea of extensions and intensions, does it come from linguistics? Philosophy? English? Is it widely agreed on/applied?
Why use the word “extension”? How does it relate to the typical use of the word? Like, you can extend a 10 chapter book by writing an 11th chapter. More generally, when you extend something, you add more of a thing to that thing. But here, with extensional definitions, you’re not making a thing bigger. You’re just… giving examples of it. So I have a sense that something like “example-oriented definition” would be more appropriate than “extensional definition”.
Same with “intensional definition”. I think “intensional” relates to “intense” rather than “intent”. But I don’t see what it has to do with intensity or intentionality.
The idea of distinguishing between symbols and referents here makes sense to me. Like, yes, definitions are symbols not referents. So in some sense they are maps not territory. But I feel like an actual definition is supposed to be complete. Yes, especially for extensional definitions, the set of examples that fit is usually going to be too large to fit on a piece of paper, but I feel like that just means that the definition is incomplete. Not that definitions themselves are supposed to be incomplete.
“you can’t control the concept’s entire intension because it’s applied sub-deliberately”. I really like this. I’m thinking about it as opposed to a computer program. In a computer program, you could have one statement saying let name = 'alice' and then, later on, have another statement saying name = 'bob'. And boom: you just changed the “definition” of name. But with humans, it’s not so simple. It’s more wishy-washy. Using this analogy, if computers behaved like humans, it’d be something like ”name? That’s gotta be 'alice'. I’ve accessed name so many times and it’s always been 'alice'.” Or other times, ”name? Hmmm. I know it used to be 'alice', but I remember it being reassigned to something else. What was it reassigned to? Oh yeah, 'bob'.” In other words, the computer would have a hard time finding the correct value. Sometimes it’d mistakenly use an old, incorrect value. Other times it’d find the correct value, but only after some time and effort. Sorta like a busted cache. So yeah, when you redefine an English word, I guess you gotta keep in mind that people already use caches, you’d need to invalidate all of these caches, but in practice that won’t happen, so you’re gonna get people who use the old and now incorrect value a lot, and even when you avoid this, it’s going to mean that people can’t read from the cache anymore, so reads are going to take longer, and it’s especially going to take longer to populate the cache with the new value.
I find myself always struggling with these concepts, coming back to this post, kinda-sorta understanding it, but still rather confused. Some questions and comments:
I’ve never heard this before. Where does it come from? Like, the idea of extensions and intensions, does it come from linguistics? Philosophy? English? Is it widely agreed on/applied?
Why use the word “extension”? How does it relate to the typical use of the word? Like, you can extend a 10 chapter book by writing an 11th chapter. More generally, when you extend something, you add more of a thing to that thing. But here, with extensional definitions, you’re not making a thing bigger. You’re just… giving examples of it. So I have a sense that something like “example-oriented definition” would be more appropriate than “extensional definition”.
Same with “intensional definition”. I think “intensional” relates to “intense” rather than “intent”. But I don’t see what it has to do with intensity or intentionality.
The idea of distinguishing between symbols and referents here makes sense to me. Like, yes, definitions are symbols not referents. So in some sense they are maps not territory. But I feel like an actual definition is supposed to be complete. Yes, especially for extensional definitions, the set of examples that fit is usually going to be too large to fit on a piece of paper, but I feel like that just means that the definition is incomplete. Not that definitions themselves are supposed to be incomplete.
“you can’t control the concept’s entire intension because it’s applied sub-deliberately”. I really like this. I’m thinking about it as opposed to a computer program. In a computer program, you could have one statement saying
let name = 'alice'and then, later on, have another statement sayingname = 'bob'. And boom: you just changed the “definition” ofname. But with humans, it’s not so simple. It’s more wishy-washy. Using this analogy, if computers behaved like humans, it’d be something like ”name? That’s gotta be'alice'. I’ve accessednameso many times and it’s always been'alice'.” Or other times, ”name? Hmmm. I know it used to be'alice', but I remember it being reassigned to something else. What was it reassigned to? Oh yeah,'bob'.” In other words, the computer would have a hard time finding the correct value. Sometimes it’d mistakenly use an old, incorrect value. Other times it’d find the correct value, but only after some time and effort. Sorta like a busted cache. So yeah, when you redefine an English word, I guess you gotta keep in mind that people already use caches, you’d need to invalidate all of these caches, but in practice that won’t happen, so you’re gonna get people who use the old and now incorrect value a lot, and even when you avoid this, it’s going to mean that people can’t read from the cache anymore, so reads are going to take longer, and it’s especially going to take longer to populate the cache with the new value.The concept of “extensional“ and “intentional” definitions is a traditional distinction in philosophy and logic.