DJT: I recognise that this is your perception of my comments.
Let's pretend for a moment that you are right. It would be a very easy
perception for you to dispell: simply provide some concrete support for
your assertions. Yet to date you have refused to do so, even in this latest
reply of yours. I believe it's because you have none to offer; then in the
absence of such support your assertions are nothing more than idle
speculation. If I am wrong, prove it: provide some concrete support.
KLOB: No one has ever denied that abiogenesis has unanswered questions; we
simply deny that these unanswered questions are fatal, especially since the
questions we have been able to answer convince us that abiogenesis did occur
on the early earth.
DJT: You have taken me to task for not being specific enough. As someone
who is not convinced by the chemical evolution scenarios, I would like to do
the same to you. What are these "questions that we have been able to
answer"? If I knew what aspects of the research you find convincing, I
might be able to interact more substantially with you.
Throughout this discussion you have used a number of tactics to avoid the
point under discussion: can you provide any concrete support, or at least a
testable causal mechanism, for your assertion that there would have been
insufficient time for abiogenesis to occur. This is simply another attempt,
namely trying to turn the tables to force me to go on the defensive. There
are no "aspects" of abiogenesis research that I find more convincing than
others; I find all the viable research equally convincing. And since the
supporting evidence for abiogenesis is well documented, it is not absolutely
necessary for me to take the time to describe it all here, on this list, in
the detail necessary for you to understand why you should be convinced by it
as well. It would in fact be easier for you to answer your own question by
conducting a literature search, and since you do not find "scenarios"
convincing I would suggest avoiding newspaper and magazine articles and
concentrating instead on scientific journal articles found using a journal
database like MedLine or Entrez.
To answer your question, however, I believe we can use Lehninger's essay on
abiogenesis in the 1970 edition of his textbook _Biochemistry_ to provide us
with an outline of specific steps or stages that would have to be
accomplished. Though dated and in some places obsolete, as a general
theoretical discussion I believe it is still very relevant. He begins by
defining two assumptions that make up what is called the _principle of
evolutionary continuity_: cells arose as a series of small steps rather
than in one large single step, and that each step had a reasonably high
probablity of occurring in terms of the physiochemical laws.
Two testable consequences of this principle are that some of the most vital
biomolecules necessary for modern metabolic systems must have emerged early
in abiogenesis and did not undergo any further change, and that some of the
steps in abiogenesis should be observable in the laboratory. The first
prediction has been largely verified by such experiments as Miller-Urey and
such observations as the discovery of amino acids in meteorites and in
interstellar gas clouds, whereas the second prediction has been proven
beyond a reasonable doubt (at least among biologists/biochemists).
He also proposed three major stages in the process of abiogenesis: the
formation of the basic groups of biomolecules; the acquisition by complex or
polymeric biomolecules of specific function; and the integration of these
functional biomolecules into a simple metabolic system.
The first stage has largely been addressed by various mechanisms that
demonstrate how stable biomolecules as well as their precursors could have
been abiotically synthesized under a wide variety of conditions, from
interstellar space to deep inside the crust. The second stage has been
addressed by mechanisms such as thermal, chemical, cryogenic and solid state
condensation, while the third stage has been addressed by coacervation,
proteinoid microsphere formation and lipid encapsulation.
Stage one has for all intents and purposes been proven beyond reasonable
doubt; what debate there is centers on which mechanisms were most
significant at what times. Stages two and three are strongly and weakly
verified, respectively, and still have unanswered questions, but so far no
experiment that contradicts the principle of evolutionary continuity has
ever been done.
DJT: In order to demonstrate the inadequacy of say 650 Ma time for
abiogenesis, I need to be informed about a viable mechanism.
KLOB: You have been informed about several in the past; if memory serves,
your usual response was simply to repeat your assertion that there would not
be enough time to allow abiogenesis to occur, with vague references to
bolide impacts and the supposed difficulty of creating complex biomolecules
and metabolic systems. At no time have I ever seen you present a detailed
testable causal explanation, backed up by concrete evidence, of why there
would be insufficient time for any proposed mechanism of abiogenesis to
work.
DJT: This seems to me a bit like being required to interpret
Nebuchadnezzar's dream!
If you say so, but scientists do this kind of thing all the time. It's the
only effective way to disprove a theory: propose a counter-theory that
demonstrates that the original theory cannot work.
DJT: I admit to being inadequate to supply such a testable causal
explanation.
I admire your rhetorical style; this statement allows you to avoid having to
deal with the topic directly while at the same time not disavowing your
basic position. However, I will take what I can get. Since you have
admitted that you cannot propose a testable causal explanation that would
demonstrate the insufficiency of time for abiogenesis, then to paraphrase
Neal Roys, without a testable mechanism, the concept of the insufficiency of
time for abiogenesis does not qualify as science, but rather is an
untestable philosophical claim.
However, you could still rescue it from oblivion by providing some concrete
support.
DJT: in the absence of a viable mechanism, the prediction must be that
abiogenesis cannot happen on Earth - no matter how much time is available.
KLOB: Ignoring for the moment that this is a classical example of the
appeal from ignorance fallacy (no mechanism has been found, so abiogenesis
must be false)....
DJT: I like to think of it as an argument from knowledge.
The absence of information is not knowledge, it is ignorance. You said, "in
the absence of a viable mechanism [for abiogenesis]"; you did not say, "in
the presence of a viable mechanism that demonstrates abiogenesis is
impossible". As such, you are assuming that ignorance (i.e., a lack of
information; e.g., the absence of a viable mechanism for abiogenesis) can
prove a concept wrong; this is the entire basis for the appeal from
ignorance fallacy.
DJT: After many decades of intensive research, we seem no nearer the goal.
The research shows an increasing divide between life and non-life.
I realize that that is your view, based on wishful thinking, but an unbiased
examination of the scientific literature deomnstrates the exact opposite.
You'll find out when you do the literature search I suggested above.
KLOB: ...you have implied this argument even when specific mechanism have
been proposed. As such, it seems to me that you believe the main objection
to abiogenesis is a lack of time. So I ask again: what testable causal
mechanism backed up by concrete evidence do you have that demonstrates that
there would have been insufficient time for abiogenesis to occur?
DJT: No. I am not saying that the MAIN objection to abiogenesis is a lack
of time. I am saying that it is a constraint on theories.
Except that you have (to my knowledge) never mentioned any other objection
except a lack of time. I wanted to be charitable and assume that you did
have other objections, but since you never mentioned them I also assumed
that the lack of time was your main objection. If it isn't, I'm curious as
to what is.
Regarding the concept of insufficient time, however, this canard is based
more on a purposeful misreading of scientific opinion than anything
concrete. Let me explain.
Back when the earliest fossil evidence for any living organisms were the
fossils of the Cambrian explosion, many evolutionists believed that
abiogenesis was difficult and would require a great deal of time, but that
once life appeared, metazoan life developed very quickly. Since geological
evidence of the earth before 650 million years ago was also extremely thin,
there was no serious objection to the idea that abiogenetic conditions had
predominated for billions of years. Even when geological evidence began to
show that neutral atmospheres had predominated since 4 billion years ago,
abiogenesis was still believed to have been working during that time.
However, some evolutionists suggested that since the known physiochemical
laws dictated that many abiogenetic steps should in fact have occurred
quickly, in fact life may have arisen much earlier than previously thought.
Then discovery of fossil bacteria 2, then 3, then 3.5 billion years old,
verified this view. Almost overnight the paradigm shifted to the belief
that abiogenesis was easy, perhaps inevitable, and that the development of
metazoan life was difficult. As such, long before the new data being
reported on this list had shrunk the available time for abiogenesis down to
650 million years, abiogeneticists had already convinced themselves that
abiogenesis could -- in fact did -- occur within an amount of time as short,
if not shorter, than this.
However, people like David are sort of stuck in a limbo between paradigms.
They still believe the old paradigm's demand for billions of years for
abiogenetic mechanisms to work, then use the evidence of the new paradigm to
try to demonstrate that there had not been anough time. In point of fact
the new paradigm is based on the realization that abiogenesis in fact seems
to have happened very quickly (with regard to geological time) and that the
known mechanisms could have easily accomplished this within the allotted
time.
David may not want to believe this, but if he were to read the scientific
literature as I have suggested, and not just newspaper and magazine
articles, he would eventually discover the truth of what I am saying.
KLOB: You don't need to know a specific mechanism to answer this question;
let me give you three possible scenarios.
DJT: I take it that you are seeking some specific line of argument from me
along the lines of these three scenarios.
Something like that. In any event, I was trying to demonstrate the proper
scientific method of dealing with this subject. If you are convinced (or
even just suspect) that there was insufficient time for abiogenesis to
occur, you propose a testable causal mechanism that would demonstrate this.
Then you go out and test it. If however, you simply say, "There wasn't
enough time," then sit back and wait for your colleagues to try to convince
you otherwise by proposing mechanisms to you, you'll have a long wait. In
fact, the response you are likely to receive is something like: "You don't
think so? Fine; knock yourself out. But without any evidence or testable
mechanism to back up your opinion, that's all it is, just an opinion." And
as you should know, opinions are no substitute for facts, theories or
experiments.
DJT: I have no appetite for this, because the logic of the argument is
empty unless a specific mechanism of abiogenesis is in mind.
Trying to disprove a general concept by disproving individual mechanisms is
a bit like trying to kill a great white shark with a fork. If you poke
enough holes in it it might eventually bleed to death, but it would be a
long, laborious process, and the shark is likely to eat you before you do
any significant damage. If you want to kill a shark, you will have more
success using a method that affects the animal as a whole, such as
asphixiation, poisoning, electrocution or blowing its head off with a
cylinder of compressed air.
Similarly, if you want to disprove a scientific concept, you would be more
effective attacking the concept as a whole rather than its individual
mechanisms. It's possible to have a concept with no mechanisms, but if you
have no concept, you cannot have any mechanisms. It's as simple as that.
DJT: My original point related to the time constraints within which
abiogenesis theories must operate.
Then surely there must be a minimum time period for abiogenesis to be
viable, regardless of mechanism. If you can show by concrete means -- or
propose a testable causal mechanism that if true would demonstrate -- that
the time period permissible for abiogenesis is too short to account for "the
origin of life" on earth according to the principle of evolutionary
continuity, then individual mechanisms would be irrelevant. And it seems to
me that you are trying to do just that, what with your occasional reports of
earlier evidence for life or later evidence for the cessation of
planetessimal bombardment. As you admitted yourself in previous posts, you
feel it is important to report how the time needed for abiogenesis is
steadily decreasing. All I am asking for is concrete evidence that even 650
million years is too short.
DJT: I have followed Crick in his assessment of the achievements of the
abiogenesis research - he did not find the argument vague and neither do I.
KLOB: This is another fallacy: the appeal to authority. Crick is making
the same mistake you are; the fact that he is Francis Crick, co-discoverer
of DNA, does not change his error into truth.
DJT: I was not so much appealing to authority as suggesting that I was in
good company with someone who is generally regarded as a leader in science.
That is exactly the appeal to authority: "I must be right because Dr.
Benton Quest -- a leading scientist -- says the same thing I do." Except
that if Dr. Benton Quest is wrong, the fact that he is a leading scientist
does not make him right. And if he is simply stating an opinion, the fact
that he is a leading scientist does not turn his opinion into data.
I would also point out that Watson opposes Crick's assessment. Since Crick
is a physicist and Watson is a biochemist, if I had to choose which
"authority" to believe, it would be Watson.
DJT: The conclusions that I have come to are not ones that should be
referred to as an "appeal from ignorance".
They are if they are based on unanswered questions and not the wrong
answers. By that I mean, if the questions are simply unanswered, rather
than providing answers that contradicted abiogenesis, you are basing your
conclusions on ignorance (i.e, a lack of information) rather than knowledge
(i.e., the presence of information).
KLOB: If by "solved" you mean a detailed protocol of how abiogenesis
actually occurred, containing exact details of what happened when and how,
you are right. In fact, I will go one better: I assert that such a
protocol would be impossible to figure out, so the problems would in fact
never be "solved".
DJT: Of course. We agree.
Except that you will contradict yourself in a moment.
KLOB: If, however, by "solved" you mean that we have a number of viable
mechanisms that demonstrate how abiogenesis could have occurred under
certain sets of conditions, and that we have evidence that those conditions
prevailed on the earth at certain points in time for certain periods of
time, then you are wrong.
DJT: Nevertheless, this is what I mean.
Except that in a moment you will contradict yourself.
KLOB: We have enough evidence to demonstrate that abiogenesis is not only
likely, but probably inevitable, and we have good ideas as to how to
proceeded. There are still unaswered questions, but the general concensus
among those who do research in abiogenesis is that most of the problems have
in fact been solved.
DJT: This is the most optimistic assessment of abiogenesis that I have ever
read!
I don't doubt it, since you appear to be rather biased in your reading.
However, this is not my assessment; I am simply repeating the assessment of
experts in the field of abiogenesis, an assessment that is based on fact,
not on opinion.
DJT: I would be interested to obtain some quotations from you to
demonstrate that this is, indeed, the way the abiogenesis research community
view things.
Sorry, that would involve a number logical fallacies, including appeal to
authority and anecdotal evidence. Besides, the sources from which I
obtained this concensus -- unlike newspapers and magazines -- do not lend
themselves to sound-bite quotations like you favor. They are scientific
review articles and reference books. In them you won't find statements
like, "The concensus of the scientific community is that this is how
abiogenesis worked." Nor are you likely to find statements like, "Based on
a review of all of the available research, this is the most likely mechanism
by which abiogenesis occurred." What you will find, however, are attempts
to develop patterns from the research, patterns which would then be used to
create new hypotheses that are based on the research as a whole rather than
on any one report. This is the concensus I meant; not of opinion, but of
research. And you can discover this concensus for yourself, just by reading
the scientific literature.
The really cute part to all of this is that two scientists who oppose one
another's theories can discover that, when combined with other research,
their theories are in fact not mutually exclusive like they thought, but
complimentary.
DJT: In exchange, I offer below some recent items from BBC online,
demonstrating that there is little consensus as to where the solutions are
to be found.
This is where you contradict yourself. You are implying that the following
mechanisms -- cometary delivery, hydrothermal vent synthesis and solid state
synthesis -- are mutually exclusive; i.e., that they cannot all be right,
and that the verification of one will automatically refute the rest. (It is
irrelevant whether you believe this yourself or are simply repeating what
the invidual research teams believe; you are using them to try to
demonstrate that there is no concensus contrary to my claim otherwise.)
This implication is actually more in keeping with the philosophy of the
first possible definition for "solved": there is only one mechanism that
can exactly explain abiogenesis. In other words, by trying to demonstrate
that there is no concensus by describing what are suppose to be three
mutually exclusive mechanisms, you are actually arguing that by "solved" you
mean a single precise detailed protocol for how abiogenesis occurred. The
philosophy of the second possible definition, however, would argue that
these three mechanisms are not mutually exclusive; that they can be (and in
fact have been) integrated into an overall theory of possible mechanisms
operating simultaneously or sequentially under certain sets of conditions.
As such, if you truely meant "solved" as in the second definition, rather
than offer these mechanisms as evidence of a lack of concensus of opinion,
you would have recognized that they could be combined into a concensus of
mechanism. In which case, if you wanted to prove that such a concensus is
not possible, you would have been better off providing evidence (not
opinion) that demonstrated that the three mechanisms could not be
integrated.
Kevin L. O'Brien