I don't think you can get a semantics (above syntax) by referring to
some hypothetical external primitive world, which btw is what I would
like to explain (away), unless you presuppose Physicalism/Materialism.
In that case you should either abandon comp (and weaker theories) or
perhaps tell me where the Universal Dovetailer Argument +
movie-graph/Occam goes wrong, as it should in that situation.
Bruno
Le 05-janv.-06, à 19:04, Brent Meeker a écrit :
Bruno Marchal wrote:
Le 04-janv.-06, à 19:30, Brent Meeker a écrit :
Bruno Marchal wrote:
Hi John,
I think you may have problems because you are not used neither
trained in axiomatic thinking. The idea consists in NOT defining
the objects we want to talk about, and keeping just some needed
properties from which we prove other theorem.
Let me give an example with the idea of knowledge. Many
philosophers agree that knowledge should verify the following law,
and I take it as the best definition of knowledge we can have:
1) If I know some proposition then that proposition is true
2) If I know some proposition then I know that I know that
proposition
3) If I know that some proposition a entails some proposition b,
then if I know a, I will know b.
But that doesn't capture meaning of "know".
But nobody knows or agree on the *meaning* of "know", that's was my
point. If *you* think it leaves something out, for a mathematician it
means that you agree with the definition!
And then you propose a stronger theory by adding 4:
It leaves out 4) If I know some proposition then I have experience
causally connected to the fact that makes it true. See c.f.
Gettier's paradox.
Now, that "4" *is* problematical because it refers to a undefined
notion of causality, which itself can only be defined axiomatically.
Bruno
It's undefined, and it's definition is problematic, but I don't see
why it can *only* be defined axiomatically. ISTM that some things
must be defined empirically (i.e. ostensively) otherwise we have only
syntax and no semantics.
Brent Meeker
http://iridia.ulb.ac.be/~marchal/