Science and Christian Belief,
Vol. 17, No. 2, 15 October 2005,
FITNESS OF THE UNIVERSE
FOR A SECOND GENESIS:
Is it Compatible with Science and Christianity? (*)
The Abdus Salam ICTP, Strada Costiera 11, 34014 Trieste, Italy,
Instituto de Estudios Avanzados, Caracas, Republica Bolivariana de Venezuela
Phone: int. +390-40-22 40 392
The two questions implied in the subtitle of the present work require special attention: the compatibility of a Second Genesis with science is the subject matter of astrobiology, while the compatibility of a Second Genesis with religious belief, especially with Christian belief, lies within the domain of natural theology. Christianity inherited the simplicity of Jewish theology. Monotheism does not present us with any particular stumbling stone for incorporating the emergence of life beyond the Earth. The concept of the fitness of the cosmos for the origin, evolution and distribution of life is relevant for our discussion: the American scientist and philosopher Lawrence Joseph Henderson introduced this concept in science at the beginning of the 20th century within a more limited scope. This issue has implications on theoretical and moral philosophy, but we are particularly concerned with implications that astrobiology may present to natural theology. The topic of the relationships between science and religion has been discussed in depth particularly since the Enlightenment 1. Our discussion will remain within the natural boundary of science. We are concerned with the question of whether the evolution of intelligent behaviour is inevitable, given what we know from the new science of astrobiology.
astrobiology, solar system exploration, divine action, Christianity, convergence in science.
(*) Article based on a contribution to Fitness of the Cosmos for Life: Biochemistry and Fine-tuning, An Interdisciplinary, Exploratory Research Project Commemorating the 90th Anniversary of Lawrence J. Henderson's "Fitness of the Environment" 2, Harvard-Smithsonian Center for Astrophysics, Harvard University, sponsored by the John Templeton Foundation, October 11-12, 2003.
(+) The current positions of Professor Julian Chela-Flores are: Staff Associate ICTP, Trieste, Research Associate, Dublin Institute for Advanced Studies and Profesor Titular, Institute of Advanced Studies, Caracas. Republica Bolivariana de Venezuela.
1. A Second Genesis, or the origin of life elsewhere in the universe
In his book Religion and Science Bertrand Russell isolated the main problem at the basis of the question whether our universe is fit for the emergence and evolution of life. At a time when Alexander Ivanovich Oparin was struggling to understand the origin of life on Earth, Russell wrote: 1
"The three centuries that have elapsed since the Giordano Bruno suffered martyrdom for believing in the plurality of worlds have changed our conception of the universe almost beyond description, but they have not brought us appreciably nearer to understanding the relation of life to the universe".
Astrobiology is a broad discipline
that can guide us into an understanding of life in the universe.
In fact, it is the correct tool for the search of answers that
science can provide regarding the question of the fitness of the
universe for the emergence and evolution of life.
In this context we can attempt to formulate questions that are of interest beyond science:
Does complex chemistry offer evidence of purpose?
The intimately related questions
of the anthropic principle and fine-tuning in living systems 2
are questions that would be simpler to understand with more than
a single Genesis.
On the other hand, our religious traditions go back to Jewish theology: there is a sole omnipotent God who created heaven and earth, and subsequently life on earth. This view of our origins has traditionally been referred to as (a 'first') Genesis. But revelation through the scriptures never raises directly the question of the plurality of inhabited worlds. There is no incompatibility between religious tradition and the possibility that we may not be alone in the universe. What is exciting about the emergence of the new science of astrobiology is that we can explore the possibility that the evolution of intelligent behaviour may be inevitable in an evolving cosmos. We shall refer to the possibility of life originating elsewhere in the universe as a 'Second Genesis' 3.
An aspect of these reflections should be highlighted from the beginning: Our lives are short and we crave for an answer to the question Are we alone in the universe? No intelligent signals have been identified after almost half a century of searching for life in the universe. This investigation has been carried out through windows of the electromagnetic spectrum. Nevertheless it should be emphasized that considerable technological progress has been achieved in the techniques being used since the SETI project began in the middle of last century. But technology has not been the only field of the space sciences that has progressed in recent years. The exploration of the solar system has also been remarkable with a fleet of missions that are capable of detecting microscopic life.
The search for extraterrestrial life was attempted for the first time on the surface of Mars a quarter of a century ago. The Viking missions were capable of detecting microbial life. Sadly, the results were not convincing to most scientists. The search still continues today with Mars being the present target of several space missions from NASA, ESA and Japan.
Yet given the harsh conditions for the survival of extremophilic microorganisms on the Red Planet, the best digging equipment with present technology is still unable to probe as far as the more likely sites, deep underground, where we expect abundant liquid water to be present.
2. Is the science of biology the right tool to discuss a Second Genesis?
In order to consider the question
whether a Second Genesis is possible, we should first decide if
the science of biology would be the right tool to apply in order
to find out whether there is life anywhere in the universe. Indeed,
some issues have been discussed in the past regarding the universal
nature of biology in general, and biochemistry in particular:
Firstly, life may be a cosmic imperative 4. A somewhat different
approach is due to Francis Crick 5: In the 'directed panspermia'
hypothesis life can emerge in some solar systems by directly sending
microbial organisms to barren planetary or satellite environments.
Secondly, multicellular life may be a rare phenomenon in the cosmos, although the existence of microbial life may still be widespread 6. Finally, a third related issue is the possibility that evolution of intelligent behaviour may be just a question of time (and preservation of steady planetary conditions), and hence ubiquitous in the universe. Darwin's theory of evolution is assumed to be the only theory that can adequately account for the phenomena that we associate with life anywhere in the universe 7.
We argue in favour of the inevitability of the origin and evolution of life. We assume that Darwinian evolution is a universal process and that the role of contingency has to be seen in the restricted context of parallelism and evolutionary convergence 8. Convergence is not restricted to biology, but it may also be extended to other realms of science. The question 9:
"What would be conserved if the tape of evolution were played twice?"
has been raised repeatedly
in the past 9. Since all forms of life known to us are terrestrial
organisms, it is relevant to the question of whether the science
of biology is of universal validity 10, 11.
Independent of historical contingency, natural selection is powerful enough for organisms living in similar environments to be shaped to similar ends. For this reason, it is important to document the phenomenon of evolutionary convergence at all levels, in the ascent from stardust to brain evolution. In particular, documenting evolutionary convergence at the molecular level is the first step in this direction. Our examples militate in favour of assuming that, to a certain extent and in certain conditions, natural selection may be stronger than chance 12, 13. We raise the question of the universality of biochemistry, a science supporting chemical evolution.
3. Could biochemical fine-tuning be responsible for a Second Genesis?
We have assumed that natural
selection seems to be powerful enough to shape terrestrial organisms
to similar ends, independent of historical contingency. In Sec.
2 we stated in stronger terms that evolutionary convergence could
be viewed as a 're-run of the tape of evolution', with final results
that are broadly predictable. Hence, if life arises again elsewhere
in the cosmos, we would expect some degree of convergence with
the evolution of terrestrial human-level of intelligence.
One scientific approach to test the hypothesis of a Second Genesis outside the Solar System is to search for extraterrestrial intelligence (the SETI project 14, 15). One of the objectives of SETI is to test whether trends in evolution that have been observed on Earth may serve as a basis for understanding the eventual "contact" between different forms of civilizations that do not belong to the same tree of life. Natural theology, on the other hand, is the body of knowledge about religion that can be obtained by human reason alone without appealing to revelation. Trends towards larger brains that have been observed in evolution on Earth, may serve for rationalizing the concept of Divine Action in a constructive dialogue with science. The realization that randomness in evolution does not rule out the existence of evolutionary convergence encourages an integrated approach for science and religion. Such an approach will clearly avoid a confrontation between faith and reason.
Alternatively, searching for a Second Genesis inside the Solar System, the assumed universality of biochemistry suggests that biomarkers should be selected from standard biochemistry. We should decide whether the evolution of intelligent behaviour has followed convergent evolutionary pathways. In this context, we can begin testing the lowest stages of the evolutionary pathway within the solar system. We are in a position to search directly evolutionary biomarkers in the Jovian moon Europa. We have considered a set of evolutionary biomarkers if extant microorganisms are to be encountered on Europa 16.
Why do we focus our attention on this satellite of Jupiter? There are several reasons, but the main one is related to the results retrieved from the most important mission of solar system exploration that took place last century: the Galileo mission arrived in the Jovian system in 1995 and completed its work in the month of September, 2003. This mission has exposed an environment that can, in principle, support life 17. However, the most interesting case concerns the next orbital mission the Jupiter Icy Moons Orbiter (JIMO), which is being planned for next decade. It is expected to determine specific locations where the icy surface is thin enough for a submersible penetration or, if the icy crust proves to be too thick, for testing directly on the surface for the presence of microorganisms. We may conclude that within the realm of scientific research in the foreseeable future we can address the question of 'fine-tuning' in the following sense: Evolution of the cosmos, and especially biological evolution right from the biochemical level, may be 'fine-tuned' for the inevitable emergence of intelligent behaviour in the cosmos, provided there is preservation of steady planetary conditions over geologic time.
4. A Second Genesis: implications for science, theology and philosophy
One of the main ingredients
of the study of other lives in the universe is convergence of
the evolutionary process in biology. The evolution of life in
the universe, either microscopic, or even life at a human-level
of intelligence, presents no insurmountable difficulties to natural
theology. Witness to this fact is the statement made by Pope John
Paul II in the presence of the Pontifical Academy less than a
decade ago 18. Indeed, science and religion are both concerned
with the common understanding of the destiny of life in the universe.
Since these two intrinsically different cultural activities largely
address the same questions, they should, at some point, establish
a dialogue, since the search for truth from different points of
view should inevitably lead to a common objective.
What may present more of a conflict between science and religion is not the confrontation of science with a Second Genesis. Instead, a real difficulty would be the evolution of all the attributes of man, including those that are of prime importance for theology - the spirit of man. The question has been formulated a little more precisely 19:
Is a creationist theory
required to explain the origins of
the spiritual dimension of the human being?
While we are still not in
a position to answer this question, in this paper we have attempted
to explain that contact with extraterrestrial life cannot be excluded
in the foreseeable future. Knowledge, or merely awareness, of
a Second Genesis would provide us with a solid point of reference
on which to base original discussions on the implications of all
the attributes of beings that have evolved to a human-level of
intelligent behaviour. In such discussions the participants should
be scientists and natural theologians.
Yet we wish to remain within the constraints that the seminal contribution of Galileo Galilei has imposed on us. Science must remain as an experimental academic activity. Hence, the question of man's spirit and soul should, in principle, not even enter the biological discourse. However, man's spirit and soul are concepts that are relevant to moral philosophy (ethics). It may be argued that ethics and other branches of human knowledge should be integrated. The integration of biology and ethics seems particularly relevant to the dialogue of science and religion 20, 21.
Efforts towards such integration will undoubtedly help a coherent discussion of the evolution of the attributes of man. Such inquiries should include specific attributes of man that are most relevant from the point of view of theology. The subject of the philosophical and theological implications of a Second Genesis is an open problem 22. The large number of papers, books and encyclopaedia articles on the subject demonstrates this assertion. The authors of these papers have been philosophers, scientists and theologians 23-28. Such prolific output demonstrates this assertion. It is remarkable that a substantial number of theological discussions appeared in the middle of the 20th century, although the subject itself of the possible role played by the Creator in the distribution of life in the universe began at least over two millenia ago. In fact, more than 2,300 years ago humanists have speculated about the possibility that the maker of the universe (Plato, 360 BC) 29:
"distributed souls equal in number to the stars, and assigned each soul to a star.
Several theologians preceded
the current wave of enthusiasm on the topic of the nature of extraterrestrial
beings that may have reached a human-level of intelligence. The
authors of these papers that were published since the 1960s were:
T.J. Zubek, John P. Kleinz, James Harford, Daniel C. Raible, George
Dugan, A. Carr, John J. Lynch, L. C. McHugh, Angelo Perego, Joseph
A. Breig and J. Edgar Bruns (for a more detailed bibliographic
information, we refer the reader to the paper of Douglas Vakoch
30; for references to the work of previous centuries we refer
the rader to the review of the astronomer and historian of science
Francesco Bertola 31.
A question that has been repeatedly raised in the past is the following:
Should Christians expect
that a single Incarnation of Christ in Jesus is sufficient for
the redemption of all life in the universe?
This question has been discussed previously in this journal: Davis 23, suggested that it may be unnecessary to postulate additional Incarnations. Man's reconciliation with God through the sacrificial death of Christ is assumed for understanding the redemption of any beings that may have evolved to a human-level of intelligence elsewhere in the universe. Other authors agree with such a single, universal Incarnation, for instance, Ted Peters 32 and the distinguished English cosmologist and philosopher Edward Arthur Milne (1896-1950) 33.
Some of the barriers to the dialogue between science and religion can be traced back, to the fundamental question of how to read the Holy Books of the three monotheistic religions. In the 5th century, Augustine had touched on this question in his book in "The City of God" 34. In fact, Augustine discussed a clear separation of two alternative ways of interpreting the Bible: firstly, as a source of spiritual reflection, and ethical values, and secondly, as a substitute for scientific matters. In agreement with most thinkers today, Augustine encouraged us to accept the first interpretation: According to Augustine, scientific matters should not be inferred from a literal reading of the Holy Book. In cases of conflict, Augustine advocated in favour of an allegorical interpretation of the Bible, rather than as a substitute for science.
Conversely, if science were to provide irrefutable evidence of the emergence of life elsewhere (cf., Section 3), theologians could read the texts of the New Testament in a broader context 28 (Jn 10:16):
And I have other sheep that are not of the fold; I must bring them also, and they will heed my voice. So there shall be one flock, one shepherd.
On the other hand, an alternative
view in natural theology, envisages multiple Incarnations. This
approach has also received much attention. Christian theologians
in this group are Paul Tillich 35, Eric Mascall 36 and Ernan McMullin
Finally, Pierre Teilhard de Chardin (1881-1955), the French philosopher and palaeontologist, developed an interdisciplinary approach 38 to the question of redemption that has implications on the evolution of life in the universe. It has been criticized by Medawar 39.
However Teilhard's work should be seen not as an alternative to scientific thought, but as a personal effort to achieve a synthesis of his mainly theological thinking. Teilhard turned away from an exclusively scientific, or even an exclusively philosophical work, when he accepted to convert his work into a contribution to natural theology. (In the past some of the critics of "The Phenomenon of Man" have ignored the restricted scope of Teilhard's natural theology 40.) Indeed, he suggested that when humanity and the world have reached their final state of evolution, a new convergence between them and God would be initiated by a future return of Christ to judge both the living and the dead (a 'Second Coming' of Christ). Teilhard asserted that the work of Jesus of Nazareth was primarily to lead the material world to a truly cosmic redemption.
Naturalism in philosophy
is a concept used by G.E. Moore as an approach that intends to
relate the scientific method to philosophy by affirming that all
beings and events in the universe are natural. Consequently, all
knowledge of the universe, including ethics, falls within the
range of scientific investigation. The American philosopher John
Dewey 20 was a strong supporter of this doctrine.
On the other hand, Jacques Maritain emphasized the notion of a 'cosmic morality' that is independent of Darwinian evolution. His review and criticism of the views on naturalism of John Dewey is relevant if it is inserted in the context of the possible existence of life in the universe. Sadly, Maritain passed away in 1973. Since that time much progress has taken place in natural theology to sort out evolutionary biology's challenge to theology; in other words, the puzzle of God's relation to an evolutionary process that is characterized by the long history of variation, mutation and selection 41.
Some clarification of these issues has been formulated by the contemporary American theologian John Haught, who has discussed the compatibility of Darwinism and natural theology in the context of kenotic process theology 42: Process theology rejects Divine Action in terms of causality, proposing that God acts persuasively in all events, but not necessarily determining their character; kenosis means self-emptying and voluntary sacrifice on behalf of others 43.
A philosophy like John Dewey's draws our attention to the possibility that ethics may be regulated exclusively by the 'positive sciences', namely the sciences that range from physics to biology and sociology. In Dewey's integrated view of science and philosophy, it is assumed that the above-mentioned scientific disciplines should be comprehensive enough to allow intelligent beings to make ethical choices according to scientific procedures.
Maritain distinguishes the concepts of spirit (a theological concept) and nature (a scientific subject). In spite of this Maritain argues that there is room for the supernatural, as Christianity understands this word, for instance, in the interpretation of the Gospels, or more generally in the interpretation of the Holy Books 21. A criticism that has been directed to the views of Maritain, is that his arguments are based on a form of foundationalism. In epistemology foundationalism means that knowledge could be started from basic beliefs (which in turn may support other beliefs, thus providing a "foundation" upon which all new knowledge could be inferred). Such basic beliefs are assumed to be self-evident; they need not be justified by more basic beliefs. (There are two different ways beliefs are justified 44: Some beliefs are justified by being based on evidence, while other beliefs are justified even though they are not based on evidence - even though they are basic. This two-fold division of justified beliefs forms the basis for foundationalism.) Clearly, in Maritain's work and, more generally in Christian theology, some form of foundationalism may be expected to be inevitable.
However, it is important to recall arguments in favour of the viability of Christian belief on non-Foundational premises due to the work of the American contemporary theologian Alvin Plantinga. The focus of the defense of his philosophical system, known as Reformed epistemology 45-47, is to concentrate on the question: Does basic theistic belief count as knowledge if it is true? 44 Here "theistic belief" means any belief that directly entails the existence of the God of monotheistic religions. The backbone of a philosophical system that attempts to equate theistic belief with knowledge is the understanding of a postulated property that converts a true belief into knowledge. This property has been labelled as "warrant," thus the philosophical system of Reform epistemology is strongly steeped with the development of what warrant really is in the specific case of this philosophical doctrine. The English language usage of this word is 'something serving as a ground for a belief', for instance, as used in the phrase "this development gives warrant in saying that it is new". Thus Warranted Christian Belief is a philosophical approach attempting to replace foundationalism. Briefly, 'evidentialism' is the doctrine that claims that theistic belief must be based on evidence in order to be justified. Plantinga argues that when we define evidentialism as the view that theistic belief is justified only if it is based on other beliefs, it turns out that evidentialism is indeed the denial of Reformed epistemology. Plantinga discusses the relationship between evidentialism and foundationalism and argues against them. This approach opens another possible discussion of other intelligent beings on different lines from Maritain.
Although some of the views of Maritain can be criticized, especially from the point of view of the Reformed epistemology, the attributes that universal biological evolution may grant to other intelligent beings are still relevant today for the scientific search of extraterrestrial intelligence (SETI). How far can we trust that evolution will give convergent results on attributes that we already know to have evolved in human beings?
We do not wish to address in this brief paper whether the position highlighted by Dewey is tenable, or whether the opposing view of Maritain is valid, but the above arguments, and some of their criticisms, are presented merely as illustrations of the relevance of a Second Genesis to human culture, not only to the new science of astrobiology, but also to both moral philosophy, as well as natural theology.
To sum up, up to the present time the intelligibility of the universe has been a topic restricted to natural theology. The arguments presented in this paper argue in favour of bringing this fundamental topic within the frontier of science. Consequently, future exploration of the solar system, and beyond, in the search for other lines of biological evolution should be considered a priority in science, as well as in ethics, philosophy and natural theology.
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