> You may not be a vitalist in that you
> invoke vitalism, but your "physicalism" depends heavily on vitalistic
> assumptions whether you recognize it or not. You have on a number of
> occasions stated that there is a wide gulf between life and non-life,
> despite the obvious fact that everything we know about life and the
> physiochemical laws that govern it tell us otherwise. The difference
> between a stone and a living cell may appear to be obvious, but it is in
> fact a difference in degree, not kind. In the final analysis, any
> insistence that there is life and there is non-life and there is nothing in
> between is in fact a vitalistic assumption, not an observable fact.
The major difference relates to information - the stone has specified
order whereas the cell has specified complexity. More on this below.
BTW, this is not vitalism.
> You have a vested interest in
> keeping life and non-life separate. Fine, but all I ask is that you present
> some concrete evidence for this. You have had ample opportunity to do so
> and yet you have so far failed to do so. As long as you refuse to either
> support your claim or to use the accepted scientific definitions, we can
> have no meaningful discussion.
It seems to me that we have moved some way from the burden of my
original posting on this thread. I will endeavour to respond to your
comments above, but think it appropriate to revisit some of the
arguments and to develop them somewhat.
Back in 1954, George Wald estimated, in a "Scientific American"
article, that about 2 billion years was abailable for abiogenesis,
and that this was sufficient for the extremely improbable formation
of a self-replicating structure to take place. He said that "time
itself performs the miracles". This is perhaps a good starting point
for this debate. Since Wald wrote, the time available for
abiogenesis has shrunk to perhaps 550 million years, during much of
which time, the earth's surface is thought to have been bombarded
with bolides. My original contribution was to say that advocates of
abiogenesis have a tighter time constraint within which they can
work.
It is fair to say that Wald's perspective is not strongly held by
contemporary researchers. Instead of chemical evolution being a
"chance" phenomenon, a route to achieve it by the operation of
natural laws is sought. The inference is made that if conditions are
"right", the emergence of the first living structures would be
inevitable. In such a scenario, time is not perceived as a problem:
the real challenge is to identify the "right" environment and the
"right" chemicals that will allow the emergence of life. It is my
view that research in this direction has not resulted in anything
that can be called a solution.
Furthermore, this approach invites the debate as to whether the
"law" responsible for bringing about life is equivalent to "chemical
and physical law". This debate is about information and the genetic
code.
Can information be a product of "natural law"? The problem here is
that law brings order and repetition. Law produces snowflakes and
crystals, not biological information. Law produces specified order,
whereas what we observe in living things is specified complexity.
Until a viable mechanism to produce information is found, the "law"
route to abiogenesis will not deliver anything substantial in a
billion years, or two billion years, or three billion years.
I seem to have been reading books that say this for quite a long
time. It is not new - and the problems do not go away. The latest
is Paul Davies. "The fifth miracle: the search for the origin of
life" (Penguin 1998). Davies is both a theistic and a naturalistic
scientist: he is seeking a self-organising universe.
Quotes:
"A law of nature of the sort we know and love will not create
biological information, or indeed any information at all." (p.210)
"Since the heady success of molecular biology, most investigators
have sought the secret of life in the physics and chemistry of
molecules. But they will look in vain for conventional physics and
chemistry to explain life, for this is a classic case of confusing
the medium with the message. The secret of life lies, not in its
chemical basis, but in the logical and informational rules it
exploits." (p.212)
"Real progress with the mystery of biogenesis will be made, I
believe, not through exotic chemistry, but from something
conceptually new" (p.216).
Davies has correctly identified the problems, but is not yet able to
offer anything outside Law and Chance to address them. Consequently,
Davies' book will neither please the naturalistic scientists nor
most theistic scientists - though he, himself, has a foot in both
camps.
The quotations above serve the purpose of expressing my own
convictions regarding the status of abiogenesis research. People
look in vain for answers. The claims of success are, in my opinion,
a triumph of naturalistic dogma over science. From the vantage point
of today, it is sometimes difficult for some to assess the validity
of these optimistic claims. Hence my prediction: time will show that
the answers are not coming. Books like Davies' "Fith miracle" will
continue to be written.
Fortuitously, the current issue of "Science" has a review/comment on
the book: The Molecular Origins of Life: Assembling Pieces of the
Puzzle by AndrŽ Brack, Ed. Cambridge University Press, Cambridge,
1999.
The review is written by Steven A. Benner: Science, 283(26 March),
1999, p 2026. It has this conclusion:
"The Molecular Origins of Life may find its greatest value by
highlighting the inadequacies of the field. Opposing sides
frequently argue past each other, failing to engage because
they use different logic and different language. Efforts to
reconstruct ancient metabolisms by picking and choosing features
of modern metabolism are often undermined by the lack of a
coherent underlying strategy, and the book contains informative
examples of this shortcoming. Those who wish to have the latest
word on the "classical" approaches to the origins of life,
which have characterized the second half of the 20th century,
will find this volume worth purchasing. But let us hope that
the next overview of the subject goes farther."
I understand this to mean that "classical" abiogenesis research has
failed to deliver - but there are a number of exciting ideas around
now which we really are very hopeful about.
The "bottom line" message is that at this point in time we have not
even one coherent and convincing scenario of abiogensis.
Best wishes,
David J. Tyler.