I'm actually sort of fond of logical positivism (LP). In a way, a large portion of this entire work is devoted to a process that sounds like an enormous crowd chanting ``L-P! L-P! All for none, and one for me!'' Or worse, LP on steriods, LP with rabies, LP foaming at the mouth and writhing on the floor near your ankle.
Not exactly. You see, LP (taken at its face value and with its original and customary proposition) is an axiom that cannot be made consistent with any axiomatic system. For those who came in late or don't remember, LP appears to be the ultimate extension of Hume's empiricism; it incorporates the empirical process itself into the logical process of determining if any assertion is correct, any question is meaningful. It asserts that:
A statement is meaningful if and only if it can be proved true or false, at least in principle, by means of the experience5
Because of the fairly obvious connections with the scientific process, LP is a favorite proposition in science classes (especially those on quantum theory, as LP is at the very root of certain interpretations of quantum mechanics and in fact was first stated at very much the same time that quantum theory was being invented and axiomatized). In science it is often expressed as the proposition that questions that cannot be empirically answered by means of a measurement or experiment have no meaning. Curiously, questions that are perfect reasonable ones in our classical experience such as ``where is that baseball and how fast is it going'' are by this criterion meaningless in quantum theory, where one isn't permitted to ask ``where is that electron and how fast is it going''.
The notion of pseudoquestions in the work above, things that might look like questions that can be answered, but really are just sounds, verbal constructs and their associated psychological perceptions that resemble questions grammatically, is clearly ripped off righteously from LP. There, however, the resemblance ends, particularly with respect to the question of meaning. Pseudoquestions are not meaningless - we all understand them perfectly well. We just cannot answer them by means of pure reason alone, and hence their answers will always be founded at some level on an unprovable belief, on an axiom.
Any attempt to establish empirical ``proof'' as a standard of ultimate knowledge both requires dozens of axioms to establish the basis for empirical proof itself and is inevitably self-referential and hence by its own standard, meaningless, as as I will now proceed to show.
Formal Proof that Logical Positivism is Wrong
This last conclusion is really quite obvious. LP is very lovely as long as you don't use it to define meaning in anything like the way it is used in English in everyday speech, but rather in a specialized sense, heavily dependent on axioms akin to those of not just science by quantum theory (difficult science). Everyone who is (still) reading this understands perfectly well what a proposition like ``God exists'' means, at least as well as they understand what the proposition ``A star exists that is outside the event horizon of my own perception''7.
So pseudoquestion propositions like these aren't necessarily meaningless (although there may be pseudoquestions that are) - in both of these cases a cognitive process of imagination can create an understanding of the non-null information content of the propositions, in both cases I can imagine, with greater or lesser clarity and fullness, what it would be to empirically validate either one (subject to the usual vast army of unprovable axioms required to empirically validate anything), and in neither case can an experiment to validate them actually be done. Or at least not one that I am quite prepared to undertake yet, in the case of the existence of God...
By this point you, dear reader, should easily be able to understand all of the reasoning above and even figure it out for yourself. The sad truth of the matter is that nothing can be proven by means of experience, as Hume observed about two hundred years before LP was invented. This, of course, means that making a proof by experience the heart of your philosophy is a really, really bad idea, unless you're doing it as some sort of cruel practical joke on generations of students and Academic Deans, or a bored philosopher down the hall from some quantum theorists and want to have some fun stealing their practical concepts, stripping off all the unwritten axioms, and putting for the result as something new and different...(which is what I rather think is what happened).
As usual, Hume's result is perpetually and eternally forgotten by every school of philosophy that has erupted since his time. If it weren't forgotten, there would be no new schools of philosophy, of course - we could just accept the notion that we don't really ``know'' anything but that which we are perceiving now and can't really know anything but what we are perceiving now plus whatever we choose to infer on the basis of our personal axioms, and spend our philosophical energies constructively in looking for a set of axioms we can all agree upon, in living with them, in playing all sorts of games inferred and deduced from them, without the impossible burden of having to ``prove'' them right.
It's hard to blame poor Craig, poor Carnap, et. al. for LP, or to blame all the rest of the philosophers from the eighteenth century on who have tried to sweep Hume quietly under the rug. Philosophers have to eat too, after all. Still, it is the hope and intent of this work that once people come to really understand Hume and the Bullshit Nature of Rational Philosophy, they can start working on an axiomatic philosophy where we can replace the impossible notions of logical necessity, proof, and completeness with notions that really are derived from and akin to the axioms of science: degree of belief, consistency and esthetic sensibility.
Empirical proof, even the wishy-washy kind permitted by the ``at least in principle'' in the definition of LP above is ultimately founded in the metaphysical propositions known as the Axiom of Causality and all the rest. By connecting empiricism with knowledge, we conclude that we know Nothing.
Well hell, we already knew that...
On to more fun stuff about what we Don't Really Know.