The Meaning of Metaphysics
			__________________________
 
			Valentin Turchin
 
			City College
			City University of New York
			New York, New York 10031
			turcc@cunyvm.cuny.edu
 
	(This essay previously appeared in "Principia Cybernetica",
	 [world-wide-web http://134.184.35.101/MEANMET.html] 
	 September 1994, and is reprinted here by permission 
	 of the author, February 1,  1995.)


 
	A metalanguage is still a language, and a metatheory a theory. 
Metamathematics is a branch of mathematics. Is metaphysics a branch of 
physics?
 
	`Meta' in Greek means over, and -- since when you jump over 
something you find yourself behind it in space and after in time -- it 
is also understood as behind and after. The word `metaphysics' is said 
to originate from the mere fact that the corresponding part of 
Aristotle's work was positioned right after the part called `physics'. 
But it is not unlikely that the term won a ready acceptance as denoting 
the whole field of knowledge because it conveyed the purpose of 
metaphysics, which is to reach beyond the nature (`physics') as we 
perceive it, and to discover the `true nature' of things, their ultimate 
essence and the reason for being. This is somewhat, but not much, 
different from the way we understand `meta' in the 20-th century. A 
metatheory is a theory about another theory, which considered as an 
object of knowledge: how true it is, how it comes into being, how it is 
used, how it can be improved, etc. A metaphysician, in contrast, would 
understand his knowledge as a knowledge about the world, like that of a 
physicist (scientist, generally), and not as a knowledge about the 
scientific theories (which is the realm of epistemology).
 
	If so, metaphysics should take as honorable a place in physics 
as metamathematics in mathematics. But this is very far from being the 
case. It would be more accurate to describe the situation as exactly 
opposite. Popularly (and primarily by the `working masses' of 
physicists), metaphysics is considered as something opposite to physics, 
and utterly useless for it (if not for any reasonable purpose). I will 
argue below that this attitude is a hangover from the long outdated 
forms of empiricism and positivism. I will argue that metaphysics is 
physics.
 
	A detractor of metaphysics would say that its propositions are 
mostly unverifiable, if intelligible at all, so it is hardly possible to 
assign any meaning to them. Thales taught that everything is water. The 
Pythagoreans taught that everything is number. Hegel taught that 
everything is a manifestation of the Absolute Spirit. And for 
Schopenhauer the world is will and representation. All this has nothing 
to do with science.
 
	But Democritus, and then Epicurus and Lucretius taught that the 
world is an empty space with atoms moving around in it. In due time this 
concept gave birth to classical mechanics and physics, which is, 
unquestionably, science. At the time of its origin, however, it was as 
pure a metaphysics as it could be. The existence of atoms was no more 
verifiable than that of the Absolute Spirit. Physics started as 
metaphysics. This is far from an isolated case. As we shall see later, 
Thales's water and number of the [... need the ?] Pythagoreans are not 
without their counterparts in contemporary science either.
 
	The question of verifiability is a part of our understanding of 
the nature of language and truth. What is the meaning of words and other 
objects of a language? The naive answer is: those things which the words 
denote. This is known as the reflection theory of language. Language, 
like a mirror, creates certain images, reflections of the things around 
us. With the reflection theory of language we come to what is known as 
the correspondence theory of truth: a proposition is true if the 
relations between the images of things correspond to the relations 
between the things themselves. Falsity is a wrong, distorted reflection. 
In particular, to create images which correspond to no real thing in the 
world is to be in error.
 
	With this concept of meaning and truth, any expression of our 
language which cannot be immediately interpreted in terms of observable 
facts, is meaningless and misleading. This viewpoint in its extreme 
form, according to which all unobservables must be banned from science, 
was developed by the early nineteenth-century positivism (August Comte). 
Such a view, however, is unacceptable for science. Even force in 
Newton's mechanics becomes suspect in this philosophy, because we can 
neither see nor touch it; we only conclude that it exists by observing 
the movements of material bodies. Electromagnetic field has still less 
of reality. And the situation with the wave function in quantum 
mechanics is simply disastrous.
 
	The history of the Western philosophy is, to a considerable 
extent, the history of a struggle against the  reflection-correspondence 
theory. We now consider language as a material to create models of 
reality. Language is a system which works as a whole, and should be 
evaluated as a whole. The job the language does is organization of our 
experience, which includes, in particular, some verifiable predictions 
about future events an the results of our actions. For a language to be 
good at this job, it is not necessary that every specific part of it 
should be put in a direct and simple correspondence with the observable 
reality.
 
	A proposition is true if, in the framework of the language to 
which it belongs, it does not lead to false predictions, but enhances 
our ability to produce true predictions. We usually distinguish between 
factual statements and theories. If the path from a proposition to 
verifiable predictions is short and uncontroversial, we call it a 
factual statement. A theory is but only through some intermediate steps, 
such as reasoning, computation, the use of other statements. Thus the 
path from a theory to predictions may not be unique and often becomes 
debatable. Between the extreme cases of statements that are clearly 
facts and those which are clearly theories there is a whole spectrum of 
intermediate cases.
 
	The statement of the truth of a theory has essentially the same 
meaning as that of a simple factual statement: we assert that the 
predictions it produces will be true. There is no difference of 
principle: both factual statements and theories are varieties of models 
of reality which we use to produce predictions. A fact may turn out to 
be an illusion, or hallucination, or a fraud, or a misconception. On the 
other hand, a well-established theory can be taken for a fact. And we 
should accept critically both facts and theories, and re-examine them 
whenever necessary. The differences between facts and theories are only 
quantitative: the length of the path from the statement to verifiable 
predictions.
 
	This approach has a double effect on the concept of existence. 
On the one hand, theoretical concepts, such as mechanical forces, 
electromagnetic and other fields, and wave functions, acquire the same 
existential status as the material things we see around us. On the other 
hand, quite simple and trustworthy concepts like a heavy mass moving 
along a trajectory, and even the material things themselves, the egg we 
eat at breakfast, become as unstable and hazy as theoretical concepts. 
For to-day's good theory is to-morrow's bad theory. We make and re-make 
our theories all the time. Should we do the same with the concept of an 
egg?
 
	Certainly not at a breakfast. But in theoretical physics an egg 
is something different from what we can eat: a system of elementary 
particles. This makes no contradiction. Our language is a multilevel 
system. On the lower levels, which are close to our sensual perception, 
our notions are almost in one-to-one correspondence with some 
conspicuous elements of perception. In our theories we construct higher 
levels of language. The concepts of the higher levels do not replace 
those of the lower levels, as they should if the elements of the 
language reflected things ``as they really are", but constitute a new 
linguistic reality, a superstructure over the lower levels. We cannot 
throw away the concepts of the lower levels even if we wished to, 
because then we would have no means to link theories to observable 
facts. Predictions produced by the higher levels are formulated in terms 
of the lower levels. It is a hierarchical system, where the top cannot 
exist without the bottom.
 
	Recall the table describing four types of language-dependent 
activities in our discussion of formalization. Philosophy is 
characterized by abstract informal thinking.
 
	The combination of high-level abstract constructs used in 
philosophy with a low degree of formalization requires great effort by 
the intuition and makes philosophical language the most difficult type 
of the four. Philosophy borders with art when it uses artistic images to 
stimulate the intuition. It borders with theoretical science when it 
develops conceptual frameworks to be used in construction of formal 
scientific theories.
 
	Top-level theories of science are not deduced from observable 
facts; they are constructed by a creative act, and their usefulness can 
be demonstrated only afterwards. Einstein wrote: "Physics is a 
developing logical system of thinking whose foundations cannot be 
obtained by extraction from past experience according to some inductive 
methods, but come only by free fantasy".
 
	This ``free fantasy" is the metaphysician's. When Thales said 
that all is water, he did not mean that quite literally; he surely was 
not that stupid. His `water' should rather be translated as `fluid', 
some abstract substance which can change its form and is infinitely 
divisible. The exact meaning of his teaching is then: it is possible to 
create a reasonable model of the world where such a fluid is the 
building material. Is not the theory of electromagnetism a refinement of 
this idea? As for the Pythagoreans, the translation of the statement 
'everything is number' is that it is possible to have a numerical model 
of the Universe and everything in it. Is not the modern physics such a 
model?
 
	When we understand language as a hierarchical model of reality, 
i.e. a device which produces predictions, and not as a true picture of 
the world, the claim made by metaphysics is read differently. To say 
that the real nature of the world is such and such means to propose the 
construction of a model of the world along such and such lines. 
Metaphysics creates a linguistic structure -- call it a logical 
structure, or a conceptual framework -- to serve as a basis for further 
refinements. Metaphysics is the beginning of physics; it provides 
fetuses for future theories. Even though a mature physical theory 
fastidiously distinguishes itself from metaphysics by formalizing its 
basic notions and introducing verifiable criteria, metaphysics in a very 
important sense is physics.
 
	The meaning of metaphysics is in its potential. I can say that 
Hegel's Absolute Spirit is meaningless for me, because at the moment I 
do not see any way how an exact theory can be constructed on this basis. 
But I cannot say that it is meaningless, period. To say that, I would 
have to prove that nobody will ever be able to translate this concept 
into a valid scientific theory, and I, obviously, cannot do that.
 
	It takes usually quite a time to translate metaphysics into an 
exact theory with verifiable predictions. Before this is done, 
metaphysics is, like any fetus, highly vulnerable. The task of the 
metaphysician is hard indeed: he creates his theory in advance of its 
confirmation. He works in the dark. He has to guess, to select, without 
having a criterion for selection. Successes on this path are veritable 
feats of human creativity.