Mysterion - rivista di spiritualità e mistica

www.MYS ERION.it
W.R. STOEGER S.J.
72
1 (2008) 64-77
But how did life arise on Earth? And what were some of the key processes within an
environment rich in heavy elements necessary for further chemical evolution towards
life? We shall probably never know exactly how life first originated on Earth – most
experts realize that that historical event is probably forever inaccessible to our investigations.
However, it has been possible – and is become more and more so – to give an
account or how life may have originated, given what we are discovering about chemistry
and biochemistry and geology. There are various scenarios which have been suggested –
with slightly different details. But some of the overall ideas are fairly clear. It is easy to
see that once we have abundances of oxygen, carbon, iron, copper, phosphorous, sulpher,
and all the rest scattered throughout the galaxies by the explosions of dying stars
(supernovae), the interstellar material is now much different than it was before. There
are now new conditions, a much richer type of material, upon which the laws of physics
and chemistry can work. New and different macroscopic objects and microscopic objects
become not only possible, but inevitable – new types of stars, Jupiter-like planets, rocky
planets, asteroids and comets, crystals and dust of various sorts, and a wondrous variety
of molecules. And with these new objects pervading the universe, the conditions and
environment in many different localities again evolves in something different, leading in
turn to further new and exciting possibilities.
Once we have planets, asteroids, comets and cool gas clouds surrounding stars or
near stars, these become the laboratories within which new and more complex molecules
are synthesized – water, ammonia, oxides, nitrides, and even more complex organic
molecules such as formaldehyde, methane, and the more immediate building blocks for
replicating molecules essential for life, sugars, amino acids, nucleic acids. The key idea
is simple to understand – given certain conditions of temperature (cool but not too
cool!), radiation, concentrations of certain chemical compounds, equilibrium or nonequilibrium,
the processes yielding new molecules will occur in these cool dark clouds,
and on asteroids, comets and planets. And in each case, these new molecules in turn
radically alter the existing environment and conditions, and in effect constitute completely
new environments which may in some cases provide the conditions for even further
advances in chemical evolution. And so on.
In fact, these planets, asteroids and gas clouds begin to evolve in their own very
peculiar ways, depending on the ever-changing conditions which characterize them – or
characterize regions on them. As planets cool, contract, shift in their structure, develop
atmospheres, undergo episodes of volcanism, are subjected to storms, electrical discharges,
and showers of meteorities and cometary debris, they will change is certain – sometimes
radical – ways, as will also the conditions of temperature, chemical composition,
atmosphere, etc. on their surfaces. As certain types of conditions develop, what were
only remote possibilities before now become near certainties, and what were possibilities
before are by-passed and excluded from realization. New regularities and relationships
emerge among the new more complex and more highly organized entities and
systems – regularities and relationships which are thoroughly consistent with the four
fundamental physical forces we talked about in the last talk – but which directly characterize
the relationships and inherent behavior of the new entities and systems themselves.
None of what happens to any particular system or object is absolutely inevitable.