Indeed, they are almost certainly picking out the reference of ‘human’ in a more complex way. Their brain is capable of outputting judgments of ‘human’ or ‘not human’, as well as ‘kinda human’ and ‘maybe human’. The set of all things judged ‘human’ by this brain is an extensional definition for their concept of ‘human’. The prototype theory of semantic categories tells us that this extension is unlikely to correspond to an intelligible, simple intension.
he should just tell us what he really means
Well, they could say that the property they care about is “beings which are judged by Qiaochu’s brain to be human”. (Here we need ‘Qiaochu’s brain’ to be a rigid designator.) But the information content of this formula is huge.
You could demand that your interlocutor approximate their concept of ‘human’ with an intelligible intensional definition. But they have explicitly denied that they are obligated to do this.
So Qiaochu is not using ‘human’ in the standard, scientific definition of that term; is implying that his moral views do not face the argument from marginal cases; is not clearly saying what he means by ‘human’; and is denying that he is under an obligation to provide an explicit definition. Is there any way one could have a profitable argument with such a person?
Indeed, they are almost certainly picking out the reference of ‘human’ in a more complex way. Their brain is capable of outputting judgments of ‘human’ or ‘not human’, as well as ‘kinda human’ and ‘maybe human’. The set of all things judged ‘human’ by this brain is an extensional definition for their concept of ‘human’. The prototype theory of semantic categories tells us that this extension is unlikely to correspond to an intelligible, simple intension.
Well, they could say that the property they care about is “beings which are judged by Qiaochu’s brain to be human”. (Here we need ‘Qiaochu’s brain’ to be a rigid designator.) But the information content of this formula is huge.
You could demand that your interlocutor approximate their concept of ‘human’ with an intelligible intensional definition. But they have explicitly denied that they are obligated to do this.
So Qiaochu is not using ‘human’ in the standard, scientific definition of that term; is implying that his moral views do not face the argument from marginal cases; is not clearly saying what he means by ‘human’; and is denying that he is under an obligation to provide an explicit definition. Is there any way one could have a profitable argument with such a person?
I guess so; I guess so; I guess so; and I guess so.
You are trying through argument to cause a person to care about something they do not currently care about. This seems difficult in general.
It was Qiaochu who initially asked for arguments for caring about non-human animals.