Philosophy Now-Aug-Sept 2019

(Joyce) #1
12 Philosophy Now ●August/September 2019

any unprovable claim, whether about science or metaphysics or
the existence of God, is meaningless. Claims about ethics, he
said, are also unverifiable so their only meaning can be as expres-
sions of our emotional attitudes. According to verificationism,
the meaning of any statement lies in its method of verification.
Soon, Karl Popper in his Logic of Scientific Discovery pointed
out a problem with verification: no number of observations that
agree with a theory can ever conclusively prove it true. A clas-
sic example is the claim that “all swans are white.” Not even a
large number of sightings of white swans will prove this true,
but even a single sighting of a non-white swan will disprove it
(‘falsify it’). He argued that a “theory which is not refutable by
any conceivable event is non-scientific. Irrefutability is not a
virtue of a theory (as people often think) but a vice... the crite-
rion of the scientific status of a theory is its falsifiability, or
refutability, or testability.” So for Popper falsifiability, not ver-
ifiability, is the test which distinguishes genuine science from
what Popper called ‘pseudo-science’ – or ‘metaphysics’.
In the second of four BBC interviews with Bryan Magee
about logical positivism and its legacy, A.J. Ayer stressed that
the Vienna Circle’s members “saw Einstein’s work on relativ-
ity and also the new quantum theory as a vindication of their
approach.” It does seem that the replacement of Newtonian
physics by Albert Einstein’s general theory of relativity had a
revolutionary impact on logical positivism. As John Earman
writes, “a brief examination of the actual history of logical pos-
itivism reveals that one of its most fundamental inspirations is
precisely this Einsteinian revolution. The early writings of the
logical positivists – of Schlick, Reichenbach, and Carnap, in
particular – all focus on the theory of relativity, a theory whose
revolutionary impact is explicitly recognized in the course of a
polemic against their philosophical predecessors.” (Inference,
Explanation and Other Frustrations, p.85, 1992)
But does the revolution in physics that Einstein began in 1905
really vindicate the principles of logical positivism? My con-
tention is that it contradicts the Vienna Circle’s philosophy, par-
ticularly the Circle’s near fanatical commitment to the empiri-
cist methodology of David Hume, Ernst Mach and Bertrand
Russell, as well as Moritz Schlick’s principle of verifiability.
Specifically, although many of the ground-breaking and highly
exotic ideas coined by Einstein’s scientific successors – such as
white holes, wormholes, dark matter, dark energy, subatomic
strings, parallel universes, hidden dimensions of spacetime, and
gravitational waves – may appear in the mathematical equations
and calculations of theoretical physicists, in most cases no evi-
dence has yet been found in the observable Universe to confirm
their existence.


Metaphysical Philosophy or Science Fiction?
According to renowned physicist Lee Smolin, co-founder of
Canada’s Perimeter Institute for Theoretical Physics, this cur-
rent move of physics away from Vienna Circle-style empiricism
is due to “the triumph of a particular way of doing science that
came to dominate physics in the 1940s. This style... favors vir-
tuosity in calculating over reflection on hard conceptual prob-
lems” (The Trouble with Physics, 2006, pp.xxii). Mirroring the
logical positivists’ devotion to empiricism, Smolin is highly
skeptical of this ‘particular way of doing science’. It has led to


what he calls ‘the current crisis’ in fundamental physics:

“New theories have been posited and explored, some in great detail,
but none has been confirmed experimentally. And here is the crux
of the problem: In science, for a theory to be believed, it must make
a new prediction – different from those made by previous theories –
for an experiment not yet done. For the experiment to be meaning-
ful, we must be able to get an answer that disagrees with that pre-
diction. When this is the case, we say that a theory is falsifiable– vul-
nerable to being shown false. The theory also has to be confirmable;
it must be possible to verify a new prediction that only this theory
makes. Only when a theory has been tested and the results agree with
the theory do we advance the theory to the ranks of true theories”
(The Trouble with Physicsp.xiii).

In the light of this, many of the theories embraced by theo-
retical physicists today look like what Smolin calls ‘metaphysi-
cal fantasies’. One of the most prominent is the idea of multiple
universes, also known as the ‘many-worlds hypothesis’ or ‘mul-
tiverse’ theory. Different versions of it have been promoted as
an answer to puzzles in many branches of physics; it was the sub-
ject of an entire issue of New Scientist magazine in 2011, and
among its many scientific supporters was the late Stephen Hawk-
ing, who worked on it in his last published paper. But in spite of
all this, the multiverse hypothesis remains a purely speculative
theory in the sense of not being checkable by direct observation.
In fact it has no concrete empirical evidence to back it up. It
cannot be proven using Schlick’s principle of verifiability; nor
can it be falsified empirically in the way that Karl Popper believed
any truly scientific theory should be. As a mere artifact of theo-
retical speculation and/or of mathematical models, it is more
philosophy and metaphysics than testable empirical science. It
borders on science fiction.
Another dubious theory gained popularity as a result of prob-
lems surrounding the Big Bang theory, concerning the rela-
tively even distribution of matter observed throughout the vis-
ible Universe. This is something one would hardly expect to
result from a gigantic explosion of energy concentrated into a
point far smaller than an atom some 13.8 billion years ago. But
our earliest radioastronomical ‘baby picture’ of how the Uni-
verse looked 380,000 years or so after the Big Bang, shows an
even distribution of matter in every direction. To explain this
anomaly, Alan Guth and other cosmologists proposed the so-
called ‘inflation’ theory, according to which the newly created
Universe initially expanded at a rate much faster even than the
speed of light for a fraction of a second just after the Big Bang.
But this ad hoc adjustment or ‘theoretical crutch’ (to use Thomas
Kuhn’s apt phrase) fails to explain the even distribution of matter
throughout the Universe, because the debris of a Big Bang-like
explosion should still be rather unevenly and chaotically spread
even if the Universe initially grew incredibly fast. Additionally,
the new theory created other complications such as eleven
dimensions of spacetime, countless Big Bangs and, again, the
existence of numerous copies of each of us inhabiting multiple
parallel universes. Smolin remarks that, “The theory of infla-
tion made predictions that seemed dubious” (p.xi), and com-
plained that this is hardly the stuff of which Popperian science
is made:

Science

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