Re: Contradiction in Rucker?

Mitchell Porter (
Tue, 15 Jul 1997 13:47:00 +1000 (EST)

Rudy Rucker (in _Infinity and the Mind_):

> I would respond that omega is a _given_, an object of our
> immediate pre-rational experience. And to use the tools of symbolic
> logic to investigate an _empirically_ existing phenomenon...

Roderick A. Carder-Russell:

> It seems to me that he is at first asserting that the concept of
> omega exists a priori. He then goes on to speak of it further as
> an empirical phenomenon, certainly in clear contradiction of the
> first statement. Any thoughts on this? Could I be correct, or am
> I missing something in the text?

I suspect he's saying that we can directly perceive omega,
as directly as we can perceive sounds or colors - although
not through any of the five senses, but through some other
faculty of mind (e.g. "intellect" or "intuition"); and that
he will count as empirical evidence, not only sense-data,
but also "intuition-data", derived from that extra faculty.

Eric Watt Forste:

> This is the kind of thing that Kant invented the phrase
> "synthetic a priori" to cover. It looks like Rucker is asserting
> that omega belongs to the synthetic a priori, although he may
> not *intend* to have done so...

I'm not sure about this. A priori knowledge is supposed to
be had without appeal to perception. Rucker might agree that
the existence of omega is not an analytic truth, but he
might say that we only know about omega because we "perceive"
it (again, where "perceive" would have to include the alleged
faculty by which one is directly aware of mathematical