Prester John,
I don't know if you were addressing my posts or not. Seems likely. In the future, perhaps you could make it clear?
Prester John said:
So does Santa Claus exist? Prove he doesn't. Old i know but you can't prove a negative, we all know that here.
Ok, time to stretch these neophyte logician's wings. Hope I don't crash.
As I understand it, if I make the statement “Santa Claus exists”, the burden of proof on that claim is with me, and I cannot demand that an opponent prove that he does not exist. That’s the context of the well-known axiom “you can’t prove a negative”. All an opponent need do is demonstrate that the proof I provide is erroneous to counter my claim.
If I make a negative claim like “Santa Claus does not exist”, the burden of proof remains with me to prove the claim, despite the negative. The opponent still simply waits for the proof and reacts accordingly. Or, of course, the opponent can produce Santa Claus and directly disprove the claim.
To illustrate this with an easier example, I can prove that “I do not have a million dollars in my bank account“, simply by showing you an up-to-date bank statement. I’ve proven a negative.
In Pyrrho’s case, I challenged his claim that “paranormal abilities are impossible”, because he was indeed making a claim that he could not prove.
On a side note, I think your example is interesting. If you worked back and found the first fictional reference to Santa Claus, could you claim that he is just a work of fiction and thus does not exist? Would that be sufficient proof? Just asking.
Prester John said:
However it is reasonable to assume that some things are so unlikely (eg santa claus is real) , the chances of them exisiting are vanishingly small, that they are effectivly impossible . Thus we would say that santa claus does not exist and is impossible.
Wrong. “Vanishingly-small chance” does
not equal “impossible”.
Sure, in practical terms, you can regard the two distinct things as the same, for purely practical purposes. But when circumstances demand rigour (as this one does) you cannot equate the two. To do so will result in logical errors. As well, in this circumstance, you open up skeptics to the fair accusation of dogmatism, because you are asserting that the laws of physics are immutable.
bPer