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Biophysic course Ws 2006, Roma3 P.L.Luisi. From self-organization to the transition to life, from the origin of life to synthetic biology. Biophysic course WS 2006, Rome. Lecture number one: 1.Science confronting the origin of life on Earth. 1.1.Introduction:
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Biophysic course Ws 2006, Roma3 P.L.Luisi From self-organization to the transition to life, from the origin of life to synthetic biology
Biophysic course WS 2006, Rome. Lecture number one: 1.Science confronting the origin of life on Earth. 1.1.Introduction: Main assumptions of modern science. Science and the creationists The „crypto-creationists“ Paley and Dawkins Determinism and contingency
cells metabolic networks polymer complexes macromolecules biomonomers molecules atoms
The traditional definition: Science is the attempt to explain the phenomenology of the world in terms of the laws of physics and chemistry ..not the only way to explain the world
Friedrich Rolle, a German philosopher and biologist, writing about the hypothesis that life arose from inanimate matter in 1863, stated: The general reasons for this assumption are really so impelling, that no doubt soon or later it will be possible to show this in a clear and broadly scientific way, or even to repeat the process by experimentation. (Rolle, 1863)
William Paley, the Anglican priest who became famous for having introduced one of the most famous metaphors in the philosophy of science, the image of the watchmaker (Paley 1802): …when we come to inspect the watch, we perceive… that its several parts are framed and put together for a purpose, e.g. t hat they are so formed and adjusted as to produce motion, and t hat motion so regulated as to point out the hour of the day; that if the different parts had been differently shaped from what they are, or placed after any other manner or in any other order than that in which they are placed, either no motion at all would have been carried on in the machine, or none which would have answered the use that is now served by it. … the inference we think is inevitable, that the watch must have had a maker – that there must have existed, at some time and at some place or other, an artificer or artificers who formed it for the purpose which we find it actually to answer, who comprehended its construction and designed its use.
Living organisms, Paley argued, are even more complicated than watches, thus only an intelligent Designer could have created them, just as only an intelligent watchmaker can make a watch. According to Paley: That designer must have been a person. That person is GOD.
RICHARD DAWKINS THE BLIND WATCHMAKER (Norton & Co., NY1986) why the evidence of evolution reveals a universe without design Paley‘s argument ...is wrong, gloriously and utterly wrong. The analogy between telescope and eye, between watch and living organism, is false.... Natural selection, the blind, unconscious, automatic process that Darwin discovered... has no purpose in mind...it does not plan for the future, it has no vision, no foresight, no sight at all....(p.5)
Example of the flagellum: How complexity is built by biological evolution- slowly and continuosly
cells metabolic networks polymer complexes macromolecules biomonomers molecules atoms
About the philosophical framework Determinism vs Contigency in the origin of life
The deterministic view of the origin of life …given the suitable initial conditions, the emergence of life is highly probable and governed by the laws of chemistry and physics… together with the “continuity principle” no unbridgeable gap between inorganic and living matter; each stage in evolution develops continuously from the previous one, at each stage there is a continuous path backwards to the prebiotic state and forward to modern organisms Orgel; Morrowitz; de Duve
…from Christian de Duve, 1991: life arose throughout the succession of an enormous number of small steps, …each with a high probability of happening. This assumption has to be made because the alternative amounts to (accepting) a miracle The science of the origin of life has to adopt the deterministic, continuity view- otherwise it would not be possible to adopt a scientific method of inquiry
as opposite to this, the view by which: life originated as a entirely chance event as a highly improbable event as a “happy accident” comparable to the assemblage of a 747 Boeing by a tornado whirling through a junkyard (Hoyle 1981, 1993) the origin of life as an impenetrable barrier to science and a residue to all attempts to reduce biology to chemistry and physics (Popper (1972, 1982) we cannot give a causal explanation of the origin of biological organization. We have to do as if the biological organization is given by an external organizer Kant, 1790 See Iris Fry, Biol and Phyl. 10 (1995) 389
The science of the origin of life has to adopt the deterministic, continuity view- otherwise it would not be possible to adopt a scientific method of inquiry Christian de Duve Harold Morowitz And others…
...we also reject the suggestions of Monod that the origin requires a series of highly improbable events... The study of origin of life is useful only if that beginning took place under probably deterministic conditions, otherwise ...it becomes a branch of history rather than natural science... H. J. Morowitz Beginning of Cellular Life, Yale Univ. Press, 1992
…”I favor the view that life was bound to arise under the physical-chemical conditions that surrounded its birth” De Duve, 2002 We have no reason to believe that biogenesis was not a series of chemical events subject to all of the laws governing atoms and their interactions.” Morowitzt, 1991 “..Itis self-evident that the universe was pregnant with life and the biosphere with man. Otherwise, we would not be here. Or else, our presence can be explained only by a miracle…” De Duve, 2002
Other „crypto-creationists“???? Anthropic principle Panspermia SETI
“If life follows from (primordial) soup with causal dependability, the laws of nature encode a hidden subtext, a cosmic imperative, which tell them: ‘Make life! And, through life, its by-products, mind, knowing, understanding…’”. Paul Davis, 1991
THE NOTION OF PANSPERMIA LIFE AS AN UNIVERSAL IMPERATIVE
OPPOSITE TO THAT.... CONTINGENCY
WHAT IS CONTINGENCY? WHEN SEVERAL INDEPENDENT PARAMETERS OR ACTIONS OCCUR SIMULTANEOUSLY IN A GIVEN SPACE/ TIME SITUATION AND DETERMINE THE OUTCOME OF AN EVENT This replaces in the current literature the notion of chance, random event, and similar. Note that the each of the single determinants can be defined by a causal law; but there are son many of these determinants, and They have such an unknown statistical weight, that the result is unpredicted and generally not described by any single causation
WE WOULD LIKE TO THINK OURSELVES NECESSARY, INEVITABLE, ORDAINED FOR ALL ETERNITY. ALL RELIGIONS, ALL PHILOSOPHIES, AND EVEN PART OF SCIENCE TESTIFY TO THE UNWEARYING, HEROIC EFFORT OF MANKIND DESPERATELY DENYING ITS OWN CONTINGENCY J.Monod, Chance and Necessity, 1971
1. Life originated from inanimate matter as a spontan- eous and continous increase of molecular complexity. Chemical continuity principle - no transcendental principle. 2. The chemical process(es) to transition to life can be reproduced in the laboratory with the presently available chemical techniques and chemicals. 3. And this can be implemented in a reasonable (hours or max. days) experimental time span - once you know the right combination of prebiotic compounds and theconditions. 4. Since there is no documentation on how things really happened, there is no obligatory research pathway. SOME MAIN ASSUMPTIONS OF PRESENT DAY RESEARCH ON THE ORIGIN OF LIFE LIFE inanimate matter
Questions to the reader: 1. Do you accept the view that life on Earth originated from inanimate matter without any contribution from transcendent power? 2. Do you accept the idea that biological evolution is mostly shaped by contingency? If not, what would you add to this picture? 3. Are you at peace with the idea that mankind might not have existed; and with the idea that that we may be alone in the universe? 4. Do you accept the idea that a rose is made up only by molecules and nothing else?