SUO: Re: Question about Example in KR Book
Fred,
I agree with Popper's statement as a purely theoretical hypothesis:
"My thesis is that realism is neither demonstrable nor refutable.
Realism like anything outside logic and finite arithmetic is not
demonstrable; but while empirical scientific theories are
refutable, realism is not even refutable."
Exactly the same claim can be made about solipsism and nominalism.
It is possible to construct consistent theories about all observable
phenomena on a metaphysical foundation of pure solipsism, pure
realism, or pure nominalism.
What really matters is the metaphysics you use in everday life.
What metaphysics do you implicitly assume when the answer is
a matter of life or death?
A true solipsist, for example, would have no qualms about jumping
out of a window or walking in front of a speeding train. True
nominalists don't believe that the laws of physics are anything
more than summaries of past observations. They could never drive
a car because they couldn't predict what would happen if they
turned the steering wheel or stepped on the brakes.
Anybody who drives a car but claims to be a nominalist is
either a liar or a fool.
John