>>On the basis of predictive ability, which of the following would you
>>classify as science and why?
>>
>>meterology
>>economics
>>astrology
>>phrenology
>
>As I understand it, both economists and meterologists have theoretical
>models which make predictions - though these predictions are often
>probabilistic in nature and error prone. Nevertheless, the mechanistic
>models are there and their predictions can be tested (with some degree of
>difficulty and significant error) against the evidence. This is in contrast
>with astrology and phrenology which make predictions that, to my knowledge,
>are not supported by the evidence. Thus in at least a weak sense you could
>put meterology and economics under the banner "science" where as the
>remaining two would be excluded.
I guess that I would place less emphasis on prediction as a criterion by
which we decide what is and is not science. Sure, some science is
wonderfully predictive but may be poorly descriptive, while other science
may be more descriptive than predictive (e.g., we can describe but not
predict tornadoes, and for many years we could predict inherited traits, but
not describe how they were inherited). The examples I gave above all have
limitations in their ability to predict. However, we have been able to
learn about many of the mechanisms that cause metereological and economic
phenomena. We understand how tornadoes form but cannot predict when or
where they will form. We have similar knowledge about economic matters, but
have difficulty in predicting economic trends. In contrast, attempts to
determine whether astrology and phrenology could be understood in
descriptive or predictive terms have been fruitless. I simply wish to point
out that predictive ability cannot fully 'predict' what is science.
>I am wondering whether evolution and PC should be viewed in such a light.
>They may be indistinguishable on the basis of the evidence we have, and due
>to the imprecise nature of their predictions. While we may agree to call
>economics a science, due to the nature of the subject, we shouldn't claim to
>be as confident about its theories as we claim to be about sciences like
>physics and chemistry. Perhaps evolutionary theory should be viewed
>similarly - and perhaps PC is an alternative, valid model?
Absolutely. I suspect that many, perhaps not all, evolutionists would agree
that evolution science doesn't yield the same degree of confidence that we
have in organic chemistry for instance. Of course, evolution is really a
theory and therefore shouldn't enjoy such a level of confidence.
>Another thing that concerns me is that it seems to me that neo-Darwinians
>present evolution as being far more predictive and well understood than it
>really is. They seem to claim that their understanding of genetics gives a
>rigorous mechanical underpinning to Darwin's original theory. Thus, in
>their view, evolution has passed on from being like an economics theory, and
>has become a theory with status similar to physical and chemical theories.
>This claim seems to me to be somewhat unsubstanciated.
Your criticism is relevant, but since we cannot recreate macro evolution in
the lab, or observe it in nature, science is left with attempting to
determine whether the world reveals logical consequences of evolution. That
is all there is with which to work. Furthermore, science, as a whole,
operates on a very positive level. In trying to convince some group to fund
my cancer research, I write an application in which I explain what my work
has accomplished and what I plan to do in the future. I generally focus on
my positive accomplishments and on how I will continue to look for
confirmation of what I believe my research is telling me. It would be a bad
idea to say that I will try to disprove what I think my research tells us or
to focus too heavily on what my research has failed to explain. Although,
both confirmed and disproven hypothesis are informative to science, negative
data is difficult to publish, and no one would continue to fund a project
that failed to prove what it intended to show. Only projects that promise
to provide positive information are supported.
I think that given this focus on "positive science", we eventually tend to
believe as true, what we optimistically present in order to convince people
that our research is worthy of support. I think that the popular press
plays on this optimistic view of science as well when it focuses on "super"
cures for cancer, the gift of teflon from space exploration, and the like.
>Our understanding of genetics describes, in a mechanistic way, how an
>evolution-like process might work - and certainly I understand there is a
>significant amount of evidence that micro-evolution does in fact take place
>- through the mechanism of genetics. However, this understanding (our
>current level of understanding) tells us very little about _how_ powerful
>this evolution-like process actually is. In order to know how plausible the
>genetics mechanism is as an explanation of the transition from one animal
>(A) to another (B), we need to know much more about genetics than we
>actually do. We would need to consider the possible transitional pathways
>from the DNA of (A) to the DNA of (B). We would need to know the viability
>of these pathways. That is, for every transitional DNA string on a path
>from (A) to (B), we would need to know what kind of animal that DNA string
>would produce, as well as knowing how fit the resultant animal would be. To
>my knowledge, geneticists have only very limited knowledge about how a DNA
>string translates into a full blown biological system. If I am wrong on
>this I would very much like to hear about it. How much do geneticists
>know?
You ask how plausible is the genetic mechanism as an explanation for an
evolutionary process. Since we know of no instance in which an organisms'
genome does not carry the information for its body plan and physiology,
morphological differences between species can be confidently assigned to
genetic differences. To be sure, geneticists do not fully understand how
information in the DNA is ultimately conferred to structure and function.
But, we generally accept that genetic information also programs embryologic
differentiation, yet we do not know in entirety how the DNA string, while
not changing in information content, can direct great morphological changes
that occur during maturation from a single diploid cell to a multicellular
organism of great complexity.
Basically, it seems that your point here is that since the mechanism for
evolution is not sufficiently developed to remove ambiguities and to fill in
all holes, one should accept it only with a grain of salt. I agree and wish
my secular colleagues would recognize this, but read on as I explain my
perceptions of how science operates.
>But doesn't evolution effectively say "Genetics formed the animals by taking
>one animal and slightly modifying (through a genetic mechanism) to form
>another"? Sure, this explanation tells you a little more about the process,
>but there are no guarentees this process is correct.
Science rarely begins with models that are guaranteed to be correct. I
believe that it is critically important to understand that scientific
theories need the freedom to fail. There is no problem with having a theory
that turns out to be wrong. Theories provide a starting point with which to
ask questions of nature. Later, as the accumulating data increase our
understanding of nature, the original theory will be judged correct or not.
Notice that what we understand about nature can increase even if the
original theory is wrong.
I could give you
>another process which could describe the event. Eg, God went along a DNA
>molecule, bit by bit, and changed the links as he saw fit to form a new DNA
>molecule - this was the basis for his new creature (the whole procedure of
>DNA modification taking less than a minute). This is no less a description
>of how God might have done it than the genetics one.
But this IS less descriptive than genetics. It explains WHAT happened and
WHO did it, but not HOW it was done. Science describes HOW something
happens, as well as WHAT happened. Prior to this century, science also
attempted to address the character of WHO did it. Take the tornado example:
science has led to an understanding of what happens, and how it comes about.
This is much more descriptive than just attributing tornadoes to God. Of
course, a big question remains about what science can tell us about who is
behind the process.
>(You may sat to me "why suggest a supernatural explanation when a perfectly
good
>natural one exists". Well the answer is that I am yet to be convinced
>(though I might one day be) that the genetics explanation is "perfectly
>good".
Ahh. Skepticism with an open mind. May God bless both sides of you.
Yet I return to the problem that supernatural explanations are not fully
explanatory. A "perfectly good" mechanistic explanation (I take this to
mean "theory") does suggest a different type of explanation. As I pointed
out above, it is not required that a theory be a true explanation.
Sometimes, in my work, I have to make an hypothesis that I don't completely
like in order to explain our experimental observations. But I must work
with the information that is available and the less-than-adequate hypothesis
provides a starting point for accumulating more information that will,
hopefully, allow me to make a better model. Hypotheses are not cut in
stone, they are flexible and we do a lot of fine-tuning of scientific
hypothesis. This is why science is a process. Therefore, the fact that the
evolution model admits holes, does not necessarily minimize its usefulness.
I know of no other mechanistic model from which to ask scientific questions
about the history of life. However, I eagerly await the publication of
books that might address this topic that others on this reflector have promised.
You are
>>satisfied saying that God did it and stopping there. Why not pursue the
>>matter further to see if we can learn how God did it? Evolution, in part or
>>parcel, may or may not provide some answers, but it useful to have a theory
>>to test--especially since alternative mechanistic theories are not available.
>
>I accept your point. I can accept that evolution might be the means by
>which God created life - the study of origins might go down the same path as
>earthquakes. My point is that, as far as I can see, it has not gone down
>that path yet.
Agreed. And given my belief that scientific hypotheses are flexible, I
would not be surprised if alternative mechanistic models soon appear.
Neo-evolutionists claim we are already there. I have yet to
>see adequate evidence. Let us not embrace the full theory evolution
>prematurly.
Some of my colleagues have a problem here, but if the evolution model were
overturned, it would not be the first time that scientific dogma is tossed
out on its ear. Again, this seems to be a way that science goes about its
business. In the 17th century, Blaise Pascal and Rene DeCartes and others
had an ongoing argument about whether a vacuum was possible. For a while,
the prevailing view was that a vacuum was inconsistent with God's character
and, therefore, could not exist. It sounds silly to us today, but science
has been wrong before, will be wrong again and shouldn't be castigated for
this part of its nature.
You implore us not to embrace the full theory of evolution prematurely, I
agree. However, I think that it is important to realize what it means to
invest oneself in something. It is unlikely that a scientist would spend a
lifetime in this, or any area of research without being invested in it. It
is also unlikely that one would easily give up that in which he has heavily
invested. If we are honest, we admit that we all invest ourselves in
certain things, whether politics, philosophy, or theology that tend to leave
us with the belief that our views are correct and the views of others are
wrong. in reality, this says nothing about truth, and is simply a
reflection of the extent of one's investment. This is the human condition,
from which scientists and philosophical naturalists are not immune. Why
would we expect more from them, then from ourselves?
Shalom,
Steve
____________________________________________________________________________
Steven S. Clark, Ph.D. Phone: (608) 263-9137
Associate Professor FAX: (608) 263-4226
Dept. of Human Oncology and email: ssclark@facstaff.wisc.edu
UW Comprehensive Cancer Ctr
University of Wisconsin "It is the glory of God to conceal a
Madison, WI 53792 matter, but the glory of kings to
search out a matter."
____________________________________________________________________________