THE CONTEXT FOR ABIOGENESIS
By Mike Gene
Throughout human history the belief that life
can arise from non-life has existed and persisted. This belief originally
existed in the theoretical form of spontaneous generation, whereby life forms
were spontaneously generated from nonliving matter as long as the proper
ingredients were present. For example, in the seventeenth century, alchemist
Van Helmont outlines the following experiment to
demonstrate spontaneous generation:
"If a soiled shirt is placed in the opening of a vessel containing grains of wheat, the reaction of the leaven in the shirt with the fumes from the wheat will, after approximately twenty-one days, transform the wheat into mice."
But it is not only mice that can be spontaneously generated from the reaction
between soiled shirts and wheat. Bananas also seem to possess
this generative power. To demonstrate this for yourself, simply place pieces of
a ripe banana in an open mouthed glass jar on your front porch for a few days.
Then, take the jar inside and put the cap on it. Within a few days, you will
see that the banana has reacted with something in the air to spontaneously
generate flies!
Of course, if we were to better design these experiments and place a video
camera to record what happens to our jars as they sit, we would find that
clothing and wheat simply attract mice instead of generating them. And we’d
also see that our banana would provide a nice place for flies to lay their
eggs. This may seem like common sense today, but for centuries, the theory of
spontaneous generation persisted and was only slowly abandoned in the light of
better scientific experiments. The first serious attack on this idea came in
1668 by Francesco Redi, who showed that meat only
generated maggots if it was placed in a bottle that flies could access (and
thus lay their eggs). Redi showed that if rotting
meat was placed in a bottle whose mouth was covered by gauze to keep out the
flies, no maggots were generated.
When it became increasingly clear that mice
and flies did not spontaneously generate, you would think this whole notion
would have been abandoned. But along came the microscope which discovered a
whole new world of very small, single-celled creatures. The proponents of
spontaneous generation would thus concede that while mice and flies do not arise
from non-living matter, these newly discovered microscopic organisms did. In
fact, the naturalist Buffon proposed that when
microbes died, the organic molecules that were released and interacted with the
putrified substances in such a way that
whole new living microbes were spontaneously generated. The notion of
spontaneous generation thus continued its retreat into smaller and invisible
domains.
It wasn’t until the mid-nineteenth century
that the final blow to spontaneous generation would be made by French
microbiologist Louis Pasteur. Pasteur designed a set of elaborate experiments
that showed sterile broth would not grow bacteria unless the broth was exposed
to bacteria. Gunter Wachtershauser notes that as a
result of Pasteur’s experiments, biology received a central dogma that stated
"the spontaneous generation of whole living organisms from chemical
compounds, outside a living organism, is impossible." However Wachtershauser, who explores the origin of life from
non-life, would add, "It is the purpose of all inquiry into the origin of
life to refute this dogma."
Abiogenesis: A new home for spontaneous generation?
Abiogenesis is the scientific study of the origin of life where
life’s origin is explained in terms of nothing more than its antecedent and
immediate physical-chemical causes. Yet it is possible to view abiogenesis as an extrapolation of spontaneous generation.
The theory of spontaneous generation has a history of persistence where its
activity is said to be found in smaller and smaller entities. If mice are not
truly spontaneously generated from rags and wheat, then it must occur with
flies. If flies are not truly spontaneously generated from decaying meat or
fruit, it must occur with microbes. If microbes are not truly spontaneously
generated, perhaps the various parts that make up microbes are spontaneously
generated. But since we don’t see this happening, perhaps they were
spontaneously generated in the ancient and unobservable past.
It is also possible to view the study of abiogenesis as an expression of nonteleological
metaphysics. Pasteur himself noted this about spontaneous generation in his
address given at the Sorbonne Scientific Sioree on
"Heated controversies, such as those which arise today among our scientists, are all the more lively, all the more impassioned, for having their counterpart in popular opinion, which, as you know, is always divided between two schools of thought, as old as the hills; these days we call them "materialism" and "spiritualism." What a victory would be won by materialism, gentleman, if it could cite in its support the demonstrable fact that matter organizes itself, brings itself into life – matter, in which all the known forces of nature may already be said to reside.!"
Of course, the truth of abiogenesis might likewise be
viewed as a "victory" for materialism. In fact, Wachterhauser
points out that in the 1920s, the Communist party of the
The paradigm of the primordial soup became
established in the scientific community largely because of Harold Urey and Stanley Miller. In the early 1950s, Urey suggested that the ancient earth had a reducing
atmosphere since such atmospheres are found on Jupiter, Saturn, Uranus and
Neptune. The atmosphere was termed reducing since it contained lots of methane
and ammonia. Urey proposed that when such an
atmosphere was hit with some form of energy, such as lightening, the basic
building blocks of life would be generated. Thus, over time these building
blocks would accumulate giving rise to a rich, primordial soup. Miller was Urey’s graduate student. He decided to actually demonstare this hypothesis with an elegant experiment.
Miller designed an apparatus that was filled with a moist combination of
methane, ammonia, and hydrogen. These gases were then exposed to an electric
spark (simulating lightening) and the resulting products were condensed and
captured in a trap. Miller found that while most of the material generated by
this procedure was a brown tar that is irrelevant to the origin of life, it did
generate many of the amino acids used by life (Miller 1953). With Miller’s
success, research into abiogenesis truly began.
During the next forty years, dozens of Miller-type experiments were done with
various energy sources and atmospheric ingredients. And it is from the
seemingly successful results of all these experiments that the notion of a
primordial soup became established in the scientific lexicon.
Abiogenesis a fact?
In an article written for the magazine Free Inquiry, philosopher Michael Ruse
asserts that working scientists of all types would find it ludicrous to
question the belief that life arose from non-life through nothing more than the
laws of physics and chemistry (Spring 1998). In fact,
"I have tried to conform to the overriding rule that life be treated as a natural process, its origin, evolution and manifestations…as governed by the same laws as nonliving processes. I exclude…finalism, or teleology, which assumes goal-directed causes in biological processes….My approach demands that every step in the origin and development of life on Earth be explained in terms of its antecedent and immediate physical-chemical causes."
Science is more interested in coming up with
this particular type of explanation than in trying to determine what actually
happened. Teleology is excluded and methodological naturalism is asserted.
Thus, even if
Of course, it is still possible that science
has uncovered a very strong case for the origin of life without reference to
any form of intelligent intervention. But where is it? If one surveys the
scientific literature, the hundreds of college biology textbooks, and the books
written by scientists exploring abiogenesis, one will
look long and hard for any argument that outlines the "fact" of abiogenesis. That is, we may find all sorts of speculations
proposing how things might have happened, and the evidence that fits with these
scenarios, but we will not find powerful arguments establishing that abiogenesis did indeed happen, even in a scientific sense. Clas Blomberg, a researcher of abiogenesis, writes that origin of life research "is
aimed to show how it could have happened"(emphasis added/ J Ther Biol 187:541-554). And when
it is time to evaluate various speculations about the origin of life, Blomberg points out that the "primary question is not:
"is this the way it happened?", but rather, "what arguments
support the possibility that it could have occurred this way and what speaks
against it?"" As a consequence of methodological naturalism, one
begins with the belief that abiogenesis did happen
and then looks for evidence to outline how it could have happened. There is
nothing inherently wrong with this approach. It is just that it is not very
helpful to one who doesn’t already possess the belief that abiogenesis
did happen.
Because of its commitment to methodological
naturalism, I do not believe that science offers the definitive word on the
issue of life’s origin. Science can only offer explanations that do not invoke
intelligent intervention and is thus unable to determine if those explanations
are true. And even then, it only proposes scenarios that are possible, perhaps
plausible, or things that "could have happened." For it may very well
be true that design is behind the origin of life and this explanation is not really
part of science. But unless we can entertain and test this notion of design, we
have no way of eliminating it as a valid explanation. If we were to restrict
our inquiry to the purely scientific perspective, we would be obligated to
simply exclude any teleological explanation and find complete intellectual
satisfaction in a naturalistic speculation that proposes this or that could
have happened. Nevertheless, science is useful in that it does offer the best
possible explanations for abiogenesis that do not
invoke intelligent intervention. Therefore, if these best possible explanations
are deemed insufficient in light of all the evidence, design begins to emerge
as a more plausible alternative explanation that can fill this void. In fact,
if life was indeed designed, we might very well expect any attempt to explain
the origin of life without reference to design to face insurmountable problems. The
"Sherwood Chang opened the program with the cautious reminder that any canonical scenario for the stepwise progression toward the origin of life is still a 'convenient fiction.' That is, we have almost no data to support the historical transitions from chemical evolution to prebiotic monomers, polymers, replicating enzymes, and finally cells."
Insights from Michael Ruse
Many people often object when I argue that
belief in a non-teleological origin of life is dependent on metaphysics. Well,
I ran across an old article from my files entitled, "The Origin of Life:
Philosophical Perspectives," published in the Journal of Theoretical Biology , 1997.
It was written by philosopher and ID critic, Michael Ruse.
Although I shall dwell relatively briefly
on the present, my conclusion is that history suggests that, in origin of life
studies, one ought to be alert for more than pure science - and that
"more" may well be philosophical or metaphysical. This is not necessarily
a bad thing, but it is something to be recognized..
What drove Lamarck,
therefore, was a metaphysical belief in progress. This is, incidentally,
something opposed to the Christian belief in
Life and organization are products of nature, and at the same time results of the powers conferred upon nature by the Supreme Author of all things and of the laws by which she herself is constituted: this can no longer be called into question. Life and organization are thus purely natural phenomena…
As an aside, some of the same metaphysical
arguments used in the early 1800s are still be used against ID today. It is
this interesting to see people like Howard Van Till accuse Dembski
of flirting with deism when it is Van Till's views that would have been more
comfortably embraced by the deists of the 1800s.
we also know that the motivating factor in
Chamber's efforts was, much as with Lamarck, that of
seeing God's work through unbroken law producing His creation in an
ever-upwardly progressivist fashion.
Like Lamarck,
Chambers also embraced spontaneous generation, as he was impressed by the
perceived similarity of inorganic crystallization and life. But Chambers moved
spontaneous generation into the past and made it a "one-time" event
in a way that foreshadows current arguments about abiogenesis.
The point thus far is that both spontaneous generation, and even evolution, were notions heavily
indebted to metaphysics.
Then we get to
Let me now quote
Finally in this brief visit to the 19th
century, let me hop over the Origin to the post-Darwinian period. Surely one
would expect, given
What was at work here? Most obviously,
there was the negative factor that, whatever Darwin's hopes and intentions, he
failed to make evolution through selection into a straight professional
scientific theory, the basis for a scientific discipline. Apart from the
rejection of selection, evolution as a subject in itself continued even for the
most scientific of scientists like Huxley, to be something more and something
less than regular science. There continued to be a significant philosophical or
metaphysical dimension to the subject. In Huxley's case, evolution functioned
as a secular religion or religion equivalent, through which he could push for
the kind of society he wanted and with which he could combat those that he saw
in his way, like representatives of the established church. Others had similar
or related motives.
Positively, people were pushing, if no
longer for deism, for some later transformation. For some this was outright
materialism. For others, it was some kind of material-spirit blend, a dualism
or monism of some variety. But whatever the variant, the emphasis continued on
unbroken law and the working of its effects.
From here,
And naturally for Haeckel,
attempts to answer questions about ultimate organic origins were a crucial part
of his theorizing. Indeed his belief that one must consider such topics and
that they can be solved, virtually dropped out of his debt to
transcendentalism. A philosophy which sees deeply shared patterns between
different objects, objects often superficially quite different, and which
thinks that ultimately all of nature is interconnected, allows - or expects -
that life will come naturally from non-life. Ultimately, there is no gap to be
bridged. And French biologists arguing otherwise must simply be wrong, no
matter what experimental evidence is offered in opposition. The idea is
all-conquering.
Thus, we also see Haeckel
looking for connections between crystals and life (not to mention fudging the
data to make certain embryos look more similar than they were). And we also
find that Haeckel employed an argument that is very
familiar today:
If we do not accept the hypothesis of spontaneous generation, then at this one point of the history of development we must have recourse to the miracle of a super-natural creation. The Creator must have created the first organism, or a few organisms, from which all others are derived, and as such he must have created the simplest Monera, or primeval cytods, and given them the capability of developing further in a mechanical way. I leave it to each one of my readers to choose between this idea and the hypothesis of spontaneous generation. To me the idea that the Creator should have in this one point arbitrarily interfered with the regular process of development of matter, which in all other cases proceeds entirely without his interposition, seems to be just as unsatisfactory to a believing mind as to a scientific mind.
This argument, made in 1868, still remains
one of the most commonly used arguments by religious opponents of ID,
suggesting that many religious people have a very real theological/metaphysical
reason to reject ID (in turn, making it very hard for them to be open to it).
When
First, the rise up the hierarchy brings on
fundamental and irreversible changes in conditions, which make it impossible
for life's patterns to repeat itself. From the beginning, Oparin
denied that life could ever reappear. But now this was backed by dialectical
materialism. Second, notwithstanding the fact that life could occur only once,
there is an inevitability about the appearance of this
life. It pretty much had to happen. This is a straight consequence of the sense
of necessity or inevitability built into Oparin's
philosophy - given that dialectical materialism has its roots in Hegelian
idealism, one could probably find something overlapping with Naturphilosophie if one dug deeply enough.
Oparin believed that a kind of organic gruel -
"colloidal solution" - would form naturally in the waters of the
earth, thanks to regular law-bound chemical processes. Then, from these
enriched waters, reproducing sphere-like gels would be precipitated. These were
the forerunners of cells and from them, by a kind of process of selection, more
and more sophisticated life would be found. Such metaphysics ultimately led
to the work of Miller-Urey, which today, is of
questionable relevance.
As for Haldane, he
was among the first to propose that viruses represented a primeval life form.
Yet as
Finally, in
Certainly, if one looks at the writings of
today's participants, one has the impression that there is more than brute fact
and clean theory. It is true that people are careful about introducing (or
rather about not introducing) explicit metaphysics, because the whole area does
have reputation for unbridled speculation; but appeals to complexity and to
the regularity of nature are just as solid as they were back in the days of Chambers
and Haeckel. - emphasis added
What then is my final conclusion? Simply
that, as always in science, the guiding motto should be caveat emptor. I of all
people - a professional philosopher - am certainly not saying that one should
not accept a position because it is influenced by a philosophical position. But
in evaluating claims about the origin of life, as well as judging the surface
on the surface content, one should be especially careful to search for the (possibly
hidden) agenda, which may well be philosophical or metaphysical. As with
everything else in life, some of these positions are better than others, and
the prospective buyer should know what he or she is getting.
Thus, in the end, I would say I am on pretty
firm ground in suspecting that metaphysics do indeed play a significant role in
acceptance of abiogenesis. For the fact remains that
there is an almost universal consensus that this happened that reaches far, far
beyond the actual evidence.