Wednesday, November 26, 2008

Win Sharon's Money #7

Here is a challenge for defenders of the modern notion of a priority as a (philosophically interesting) property which is distinct from necessity and analyticity....and for people who want to eat a really lavish Felipe's burrito for free.

I will describe creatures (the doctoroids) who know contingent medical facts a priori if they know them at all. If we allow that the doctoroids do know then the example can easily be generalized to show that for any true proposition there could be creatures with faculty which delivers knowledge of this proposition a priori, and hence that all true propositions are a priori. Thus the challenge for someone who holds the modern conception will be to say *why* the doctoroids don't count as knowing in a way that a) doesn't equate a priority with necessity or analyticity and b) seems remotely principled.


Imagine that in order to save people people 6 years of medschool we engineer 'doctoroids', people who are genetically and physically altered so that they find certain true propositions of organic chemistry and medicine brutely obvious, the way that we find the claim 2+2=4 obvious. That is: they don't ask for justification of these claims, and their acceptance of what has been hardwired into them is fairly causally independent of whatever they see after they are born (e.g. they all come to believe that smoking causes cancer at an early age regardless of how they are raised and continue to believe it in the face of strong evidence to the contrary). Also these creatures don't wind up doing anything that looks like empirically checking the accuracy of their medical intuitions - they find it perfectly obvious in advance that smoking causes cancer, and if they were to encounter cases where smoking seems not to cause cancer they would treat this the way that we treat cases where there seem to be 2 apples and 2 oranges which jointly constitute 3 fruit i.e. as evidence that their observations had somewhere gone wrong.

(and here is a link to my current draft of a paper on the subject, should you *really* want to procrastinate)

2 comments:

TruePath said...

What I think this shows is merely that the notion of a priority is relative to your biological makeup. On reflection this seems reasonable since it is an epistemic concept after all.

However, what we can define is the relation P is a priori for X. Thus you can phrase what you are showing in your thesis is why we should expect that if X is a random variable reflecting our likelihood judgment (e.g. our ability to reason about scientific theories) then

P( most P's that are a priori for X are true | X is a tool using creature resulting from evolution) is high

Sharon Berry said...

"What I think this shows is merely that the notion of a priority is relative to your biological makeup. On reflection this seems reasonable since it is an epistemic concept after all."

yes. that is pretty much the skeptical conclusion in the paper draft. The only difference is I would then say that what we normally call a priori is what you would call 'a prori for normal humans'.
I'll have to think more about the thesis suggestion.