Science and Philosophy by Derek Gjertsen, Penguin, pp 296, Pounds sterling
5.95 pbk Physics and Philosophy by Werner Heisenberg, Penguin, pp 200, Pounds
sterling 5.95 pbk

AS THE word philosophy means love of wisdom, you might view the history
of philosophy as a sort of romance,numerous suitors reciting their tales
of intellectual valour, adventurous accounts of their first encounters and
subsequent courtships of the eternally desirable, yet ever elusive, Sophia.

If philosophy partakes ofromance, then does sciencerepresent a lesser
quest, the search for prosaic but more accessible goals than high philosophical
wisdom? And if philosophy is truly the ‘queen of the sciences’, then why
is philosophy so often scorned by many working scientists as irrelevant
and empty speculation? Since science seeks (and often finds)a certain kind
of knowledge,how does this knowledge differ(if at all) from the kind ofwisdom
the philosopher pursuesso passionately? Derek Gjertsen, an Oxford graduate
and former professor at the University of Ghana, asks these questions and
many more as he explores the issues that connect and those that divide philosophers
and scientists. He also attempts to disclose thedifferences that separate
thesedisciplines by examining the suggestion that science is empirical,
future-orientated, and concerned with specific problems, while philosophy
is speculative, orientated towards the past, and concerned with problems
of great generality, such as the nature of being.

Drawing on a wealth of historical incidents for evidence, Gjertsen finds
that these categories cannot infallibly distinguish between philosophy and
science. He shows that scientists are often speculative, past-orientated
and concerned with issues of great generality, while philosophers sometimes
exhibit so-called ‘scientific’ traits.

A common view of the split between science and philosophy is that philosophy
deals with problems that have no solutions: when a set of philosophical
problems becomes amenable to proof, these problems exit the philosophical
realm, and a new science is born. Gjertsen devotes an entire chapter to
this distinction: ‘Is Science Really the Art of the Solvable?’, and shows
that many ‘scientific’ problems are as resistant to solution as any in philosophy.
Concerning the nature of philosophical ‘solution’, he suggests that philosophers
have their own manner of ‘solving’ problems. Gjertsen likens philosophical
activity to progress in the game of chess – a game for which no final solution
is known. Yet chess players and philosophers, building on the work of past
masters, continue to discover novel strategies thatadvance our knowledge
of the game.

Gjertsen concludes that, although science and philosophy are certainly
different enterprises, they are too rich and interwoven to be separated
by easy criteria. Depending on the example taken, he maintains, ‘at some
points philosophy and science appear to have nothing in common, but with
a different example, they can seem to be almost indistinguishable’. Gjertsen
believes that the’exasperated contempt’ somescientists feel towards their
more speculative cousins to be misguided: the science/philosophy split is
illusory. ‘Science without philosophy is impossible,’ he says, ‘while philosophy
without science is immature.’

As an example of how philosophy can help science, Gjertsen shows how
parapsychology might be disbarred from the scientific status to which it
currently aspires on strictly methodological grounds on the basis of how
its practitioners treat instances of disconfirmation. True scientists employ
evidence that is disconfirmatory either to dismiss the alleged phenomenon
as illusory or as a positive basis for designing new kinds of experiments
to reveal the alleged phenomenon. This tendency of science to learn from
its mistakes reminds me of my experience as an industrial physicist. During
a staff meeting an angry engineer criticised the physicists, ‘When your
physics experiments work, you claim success. And when they don’t work, you
still claim to have learned something. We engineers don’t enjoy the luxury
of failure!’ Gjertsen suggests, using cases from their own literature, that
parapsychologists often fail to use disconfirmation constructively but instead
invent ad hoc excuses for their general inability to replicate one another’s
results. In so far as Gjertsen’s criticism is valid, and not just a straw-man
attack, parapsychologists would do well to pay close attention to how they
handle evidence that does not confirm their claims.

Can researchers establish philosophical truths scientifically? Gjertsen
examines the recent claim that the theorem of John Bell plus experiments
of Alain Aspect and his colleagues on correlated photons establishes a general
(and non-obvious) feature of the world – namely, that a far-reaching non-local
connection exists between the world’s apparently separated parts. Gjertsen
dismisses this claim on the grounds that correlation between two systems
does not imply connection. On the other hand, to my mind, the essence of
John Bell’s work was to show that correlations between any two systems (not
necessarily quantum) can be divided experimentally into two exclusive classes
– those correlations that can be explained without resorting to non-local
connections (all classical correlations are of this sort), and those correlations
that cannot be so explained. Experiments seem to confirm overwhelmingly
that certain quantum correlations belong to Bell’s second class. Hence non-local
connections necessarily exist in nature, a heretofore unsuspected philosophical
fact.

Gjertsen’s book does not lack the abstract reasoning found in other
philosophy books, but its real value lies in the numerous historical examples
that he uses to elucidate the triumphs and follies of scientists and philosophers
alike in their ardent pursuit of Sophia’s elusive charms. Gjertsen obviously
loves his material, and the book’s generous and lively spirit should appeal
to a wide range of readers.

More than 50 years have passed since the birth of quantum theory; numerous
international conferences are being held to celebrate this or that special
event in the childhood of the 20th century’s deepest and most successful
theory of the physical world. What better time than this to reissue a classic
collection of popular essays on quantum theory by one of its most distinguished
practi-tioners? In the first half of this century, while inquiring into
the deep structure of matter, physicists stumbled upon an aspect of nature
too strange to be explained in words (Does this sound familiar, lovers?).
Heisenberg’s essays, in Physics and Philosophy, deal largely with the question
of the adequacy of ordinary language to cope with the quantum world. ‘The
problems of language here are really serious,’ Heisenberg maintains. ‘We
wish to speak in some way about the structure of the atoms and not only
about the ‘facts’ (of atomic experiments). But we cannot speak about the
atoms in ordinary language.’

Quantum theory is a mathematical technique for predicting the results
of certain experiments on a system (described in ordinary language) given
the results of previous experiments (also described in ordinary language).
Although quantum theory does ‘represent’ the system in an abstract mathematical
fashion, it does not offer any clear image of what the system ‘is really
doing’ between measurements. Whenwe look at (observe) a system,ordinary
language suffices todescribe our observations. However, when we don’t look,
language fails to describe what (if anything) is really going on in the
world. This is the gist of the quantum dilemma.

‘The ontology of materialism,’ says Heisenberg, ‘rested upon the illusion
that the kind of existence, the direct ‘actuality’of the world around us,
can be extrapolated into the atomic range. This extrapolation is impossible,
however.’ One solution to the quantum dilemma might be to invent a new language
more adequate to the atomic realm, the so-called ‘quantum logic’ approach.
Heisenberg suggests a different strategy: ‘The concepts of classical physics
form the language by which we describe the arrangement of our experiments
and state the results. We cannot and should not replace these concepts by
any others.’ But these classical concepts cannot be applied indiscriminately
to all phenomena: quantum physics places strict non-linguistic limits on
their usage: prescribing what might be called a ‘zone of ineffability’ whose
dimensions are set by Heisenberg’s uncertainty principle. ‘We must keep
in mind this limited range of applicability of the classical concepts while
using them,’ says Heisenberg, ‘but we cannot and should not try to improve
³Ù³ó±ð³¾.’

Heisenberg’s conservative approach to the language problem of quantum
physics is reminiscent of the old notion that poetry is the art of using
words to say that which it is impossible for words to express. And indeed
Heisenberg compares the physicist’s dilemma to that of the artist. Both
are trying to describe not an objective world existing ‘out there’ but the
interplay between the world and human consciousness. It is our intrinsic
entanglement with nature, or inability to distance ourselves from phenomena
(both emotional and physical) that gives rise to ineffability zones. ‘The
two processes, that of science and that of art, are not very different,’
Heisenberg says. ‘Both science and art form in the course of the centuries
a human language by which we can speak about the more remote parts of reality.’

Most of Heisenberg’s colleagues accepted his quantum limits to ordinary
language and studiously shunned the ineffability zone. Heisenberg, however,
strained to capture the essence of unobserved reality in words (Sophia’s
true lovers often find it difficult to hold their tongues). The unobserved
world is not made of things, Heisenberg said, but of ‘tendencies’ – ‘a quantitative
version of the old concept of ‘potentia’ in Aristotelian philosophy.’ In
between atomic observations, there is nothing that is ‘really going on’.
Instead the world is better described as ‘something standing in the middle
between the idea of an event and the actual event, a strange kind of physical
reality just in the middle between possibility and reality’. Few physicists
have been able to add much more to Heisenberg’s tentative vision of quantum
reality as mere ‘tendency’.

Heisenberg’s essays are prefaced by physicist Paul Davies’s lucid summary
of quantum theory, including developments Heisenberg could not have foreseen
especially in the area of quantum connectedness. These new developments
enrich Heisenberg’s views, rather than refuting them, demonstrating the
deep physical intuition of this founding father of quantum theory. ‘The
enduring appeal of this book,’ says Davies, ‘is that it carries the reader,
with remarkable clarity, from the esoteric world of atomic physics to the
world of people, language, and the conception of our shared reality.’

Nick Herbert is a consulting physicist based in Boulder, Colarado. He
is author of Quantum Reality

WITH uncharacteristic modesty, Isaac Newton once compared himself to
a boy on the seashore picking up a few bright shells while all about him
lay the vast ocean of ignorance. Indeed the ocean-of-ignorance metaphor
suggests that the search for knowledge must be unending by its very nature,
since as we expand the island of knowledge, the perimeter of our ignorance
increases in direct proportion. The pessimistic thrust of this insular metaphor
is mitigated by the possibility that the ocean of ignorance might be bounded
or that integrative concepts can be found that capture in a few overarching
notions myriads of disparate facts – a bird’s-eye view of things not accessible
to the land-bound observer. The main message I get from The New Physics,
a comprehensive overview of our current world picture, is that physicists
seem remarkably close to mapping the entire ocean of ignorance, leaving
only puddles of perplexity for their successors.

The end of physics has been foreseen before: at the turn of the century,
Lord Kelvin pronounced physics dead, its main features already laid out.
Instead of a funeral, the 20th century witnessed an unprecedented explosion
of new physical theories and phenomena undreamt of by 19th-century physicists.
The New Physics records the aftermath of that explosion, a world view immensely
richer than Lord Kelvin could have imagined but portending a similar conceptual
closure. On the other hand, among the immense number of technical successes
described in The New Physics may lurk some tiny murkiness destined to become
the seed of the next scientific revolution. Musing about this seed, editor
Paul Davies suggests that consciousness could well be the next scientific
blockbuster.

This broad survey of 20th century science consists of about 20 essays
written at a level accessible to readers of New ÐÓ°ÉÔ­´´ by top scientists
in their respective fields. The variety of authors leads to an unevenness
of style but the authors’ eminence lends an authority and immediateness
often lacking in second-hand popularisations. The very people who are busy
creating the new physics carry the reader out to the growing edge of modern
science. It is an exciting trip.

Davies divides his survey into three parts: the ‘very large’, the ‘very
complex’ and the ‘very small’, with five or six essays devoted to each part.
Both theoretical and experimental physics are well represented; colour photographs
and line drawings help the reader to assimilate the vast amount of information
presented in this volume.

The ‘very large’ begins with an essay by Clifford Will on general relativity,
the present overarching theory of the entire Universe, including an account
of recent space-based measurements designed to distinguish Einstein’s version
of general relativity from its competitors. Steven Hawking writes about
the origin of time itself, and Alan Guth describes his inflationary universe,
a model of the early days that makes the Universe’s improbable initial conditions
appear less unlikely. Chris Isham tackles quantum gravity, the still unconsummated
marriage between gravity and quantum theory, while in a long and beautifully
illustrated chapter (‘The New Astrophysics’) Malcolm Longair describes quasars,
neuton stars, dwarfs, black holes and other strange inhabitants of the cosmos.
The fact that our information about these odd objects comes largely through
two spectral windows, radio and visible light, supplemented by satellite
peeks, suggests many more revelations as space-based astronomy matures.
Will some surprise in the sky force a new revision of physics?

The physics of the ‘very complex’ is not without its overarching theories.
Alastair Bruce and David Wallace discuss the universality of critical point
phenomena, the notion that a large number of order-disorder transitions
between order and disorder, including magnetism, fluid condensation, and
perhaps the emergence of differentiated force fields after the big bang
can be described by identical algorithms independent of the detailed forces
involved. As a fresh example of phase transition, David Thouless discusses
macroscopic ordering phenomena in two dimensions. Joseph Ford contemplates
chaos, a highly patterned indeterminism in classical mechanics that has
recently been rediscovered. Ford discusses the possible extension of chaos
into the quantum realm and entertains the reader with a full-colour bestiary
of fanciful fractal animals spawned from the chaotic inbreeding of simple
mathematical functions. Gregoire Nicolis explores the link between chaos
and self- organising systems. The physics of two such systems is also described
in great detail: superconductivity by Anthony Leggett and ordered optical
fields (‘Quantum Optics’) by Peter Knight. The book elects to treat a few
topics in great detail. For an overall view of the new science of complexity
I recommend The Dreams of Reason by the late Heinz Pagels.

Descending to the realm of the ‘very small’, Frank Close shows how present
physics can be explained in terms of quarks and leptons – are these entities
the final rungs in nature’s ladder of elementary particles? Howard Georgi
discusses the successes of the standard model (‘We have answered most of
the obvious questions and resolved all the obvious problems’) and prospects
for a grand unificating theory. John Taylor describes the use of gauge theory
as an overarching technique for unifying the forces of nature while Abdus
Salam looks to the future, asking what will the next generation of accelerators
uncover? What are the prospects for even more ambitious unification schemes
such as supergravity and superstring theory? Reviewing the foundations of
quantum theory upon which most of the new physics is based, Abner Shimony
describes the bizarre quantum concepts that physicists have reluctantly
come to accept as nature’s way of doing business. Shimony introduces the
notions of objective indefiniteness, objective chance and the recent experimental
evidence for ‘quantum entanglement’, the real existence of an enduring superluminal
connection beL tween two systems that once interacted but are now by conventional
reckoning completely isolated from one another.

Because it purports to take as its subject matter all of physical reality,
Paul Davies calls physics the most pretentious of the sciences. The New
Physics is an ambitious attempt to make the frontiers of this pretentious
science accessible to a wider audience. This book succeeds admirably in
this goal. I know of no better one-volume guide to the edges of modern physics.

Nick Herbert is the author of Quantum Reality: Beyond the New Physics.
He lives in California.