What do we mean when we talk about ‘metaphysics’? It seems inevitable that the answer to this question will be tediously complex, and yet we do possess a surprisingly neat and simple solution thanks to the work of the Austrian-born British philosopher Sir Karl Popper. In his efforts to explore the question ‘what is science?’ Popper inadvertently laid down a metaphorical stone marker which stands on the borders between science and metaphysics, providing us the option to distinguish simply between the two.
All explanations of metaphysics tend to
stray into historical sidelines; perhaps the simplest explanation of
metaphysics is to claim (unfairly!) that all the abstract nonsense philosophers
discuss with no direct relevance to every day life such as Universals, Necessity
and Possibility, notions such as Final Causes and so forth – all this is the
realm of metaphysics. One can understand quite easily why someone might have
cause to oppose metaphysics as meaningless, or at least unhelpful, given this
admittedly misleading definition.
The most infamous challenge of this kind
came from a movement known as Logical Positivism which grew out of the infamous
Vienna Circle of the 1920’s, which Wittgenstein was at first associated with, and
later went to great lengths to oppose. Enamoured with the successes of science
in the previous century, the Logical Positivists proposed that propositions
gain their meaning by some specification of the actual steps taken to determine
their truth or falsehood (the so-called verification principle). This focus on
truth values is a common property in sceptical thought. Critically, it was
the view of the Logical Positivists that metaphysics was meaningless since
everything within this domain was unverifiable.
Popper thought differently. To his mind, the success of science did not lie in it being more verifiable than metaphysics (or, for that matter, than ethics). Unlike many scientists, Popper took a decidedly cool view on induction (following Hume’s approach to the matter) and observed that it wasn’t possible to confirm a universal scientific theory as this would require absolutely complete knowledge, but that it was possible to disprove a universal theory.
The relevant flaw in induction can be shown by a simple thought experiment. Suppose we have an infinitely large sock drawer (or one with so many socks within it that it is effectively infinite). Every day, we pull two socks from this drawer, and every day both are black. We might conclude via the process of induction that the sock drawer contains only black socks. But suppose one day we reach in and pull out a white sock. This immediately invalidates the ‘black sock theory’! In the same way, a scientific theory cannot be proved to be true, but it can be falsified by contradictory evidence.
Popper advanced the idea that falsification
was a more useful criteria to apply to science than the verification principle,
since universal theories can be falsified but they can never be conclusively
proved, as with the sock drawer thought experiment. He therefore proposed that
falsification be used as a boundary condition for science, and consequently
that anything that could not be falsified belonged to the domain of
While the Logical Positivists held that metaphysics was meaningless because it could not be verified, Popper never suggested that because metaphysics could not be falsified it was without meaning. Rather, he recognised that metaphysical statements tend to imply beliefs, and therefore that anything in the realm of metaphysics is a matter for individual belief. Nothing could rationally force a change in such beliefs, at least in terms of definitely proving them false, but this was categorically not the same as claiming that such beliefs were meaningless.
By the time of Popper’s knighthood in 1965,
Logical Positivism was widely recognised as having run its course, in no small
part thanks to Popper’s contribution.
Sadly for Popper, his position that falsification could be used as a boundary condition for science was quickly under attack. Thomas Kuhn and others observed that scientists do not abandon their theories in the light of contradictory evidence, which was a central assumption in Popper’s account, and Feyerabend (who had severe personal issues with his ex-mentor Popper) went on to demonstrate that there were no lasting boundary conditions to any human endeavour, never mind science.
However, this in no way invalidates the importance of Poppers work: Logical Positivism was a particularly vicious form of intellectual fascism and Popper’s contribution to its demise is to be commended and celebrated. Indeed, it is sad that despite the collapse of this school of thought in philosophy, echoes of its influence are still found in the tacit opposition certain prominent scientists and their supporters have for metaphysics.
The issue of how to present this viewpoint
without seeming to be expressing solely my own bias gave me considerable pause
until I received unlikely aid in the form of an article in The Oxford
Companion to Philosophy on the topic ‘Metaphysics, Opposition to’ written
by Prof. E. J. Lowe of the University of Durham. This hefty reference book has
been a helpful tool in my philosophical investigations, but it is mostly
written in such a dry and inaccessible prose that I never expected to find
buried within its pages something as fiercely impassioned as the following
Opposition to metaphysics has come from both within philosophy and outside it. Logical positivism, though now defunct, was particularly hostile to what its adherents saw as the meaningless, because unverifiable, claims of metaphysics. These objections foundered on the impossibility of providing an acceptable criterion of verifiability. But the deference to empirical science displayed by the Logical Positivists is still a feature of much Anglo-American analytic philosophy, creating an intellectual climate inimical to the pursuit of speculative metaphysics… Such writers are often blithely unaware of the uncritical metaphysical assumptions pervading their works and the philosophical naivety of many of their arguments. But it is ironic that the deference shown by many philosophers to the latest scientific theories is not reciprocated by the popularizing scientists, who do not conceal their contempt for philosophy in general as well as metaphysics in particular.
Professor Lowe seems to take some delight in exploring the specifics of opposition to metaphysics (both from systems of thought equivalent to Logical Positivism, and also from cultural relativism), and in doing so demonstrates that opponents to the field do not agree on even basic metaphysical tenets, thus allowing him to conclude:
The very fact of such widespread disagreement over fundamentals demonstrates the need for critical and reflective metaphysical inquiry pursued not dogmatically but in the spirit of Kant.
Or to put it another way: since we do not agree, even on purportedly objective issues such as science, the need for metaphysics is amply demonstrated.
While Feyerabend was correct in asserting
that there are no lasting boundary conditions to human endeavour, this does not
preclude using Popper’s concept of falsification usefully. After all, the
absence of lasting boundary conditions does not mean we cannot choose to
erect boundaries wherever we wish. Indeed, if we agree to a particular
boundary it may stand (by custom if by no other means) for as long as we wish.
This, after all, is the basis by which one country distinguishes itself from
Somewhere out in the metaphorical landscape of knowledge lies an almost insignificant stone marker reading ‘Erected at the boundary of Falsification’. It was set down by Popper to mark the end of science and the beginning of metaphysics. I suggest that even if we do not wish to use it to mark the border of science, Popper’s milestone can still be usefully interpreted as saying: ‘beyond this point lies metaphysics!’