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Darwin-L Message Log 2:115 (October 1993)

Academic Discussion on the History and Theory of the Historical Sciences

This is one message from the Archives of Darwin-L (1993–1997), a professional discussion group on the history and theory of the historical sciences.

Note: Additional publications on evolution and the historical sciences by the Darwin-L list owner are available on SSRN.


<2:115>From CHARBEL%BRUFBA.BITNET@KUHUB.CC.UKANS.EDU  Fri Oct 22 17:34:04 1993

Date: Fri, 22 Oct 93 19:28:00 BS3
From: Charbel Nino El-Hani <CHARBEL%BRUFBA.BITNET@KUHUB.CC.UKANS.EDU>
Subject: Generalizations in Biology
To: darwin-l@ukanaix.cc.ukans.edu

In September 24, Brook Milligan wrote:
>Over the past year or two I have noticed a series of letters
to the editor in Nature justifying the pursuit of systematics
and taxonomy as being the basis for generalizations about
biological history. It seems that the argument is that by
studying the collections present in museums and herbaria, by
studying new collections, and by organizing the results of these
studies into a historical framework describing which events took
place in the past, that we will be able to make generalizations
about biology.>

 We would like to resume this thread asking, as did Milligan,
what form this generalization would take. We think the problem in
understanding its exact nature is, in part, a problem of defining
precisely both the *historical framework* and the word
*generalization*.
 At first sight, we could think about cladistics as one of the
possible methodologies for the construction of hypothetical
phylogenies, and, historical frameworks for generalizations
about biological history. In our discussion, we will refer mainly
to cladistics, but we expect most of our doubts to apply to other
methods of inferring phylogenies.
 We consider cladograms to be one of our most powerful tools to
understand life's history. It is not so hard to say that they can
be a basis for generalizations about it. New and more difficulty
questions, however, arise from this statement: Is a cladogram always
a hypothesis, or could it originate general conclusions about the
biological history? Or, in other words, is cladistics only a
methodology for the inference of phylogenies, or a commitment to
how things realy occurred in the past? Reification is a common
problem in modern science. The analysis of variance, for instance,
is only a statistical approach to phenomena, a representation of
causes in natural systems as being *primary*, *secondary*, etc.,
what gives rise to interactions of *first order*, *second order*,
etc. Most of the scientists use to reify these numerical components
as real forces acting among real objects. In nature, phenomena arise
from a totality of causes; analysis of variance is only a method
to work with this complexity, and the main causes, the main effects,
etc., exist only in the method, not in the reality, where all causes
act together, influencing one another in such a manner that it is
very difficulty, even impossible, to isolate them. This isolation
can be done in laboratory conditions, but the properties of the
parts in study, when discovered in experimental conditions, are not
the same they have in natural systems, simply because the properties
the parts have are determined also by the whole they are in.
 To answer our question about cladograms, we have to define what is
meant by generalizations. Our question is: Can a cladogram be the basis
for generalizations *about biological history*? We are not discussing,
for instance, the existence of generalizations steps in the construction
of a cladogram. Sure, cladistic analysis involve them. When we propose
that a group is a monophyletic one we have not observed all the specimens
belonging to the group, but only a sample of them; from a particular
context of observation, we deduce a general conclusion. We have to see,
however, that this generalization is based upon a premise, a Principle
of Uniformity. Maybe, this premise can be subject to doubt.
 Now, let's not think, however, about generalizations into the
cladogram, but, on the contrary, about cladograms as generalizations
(or basis for them) about biological history. Eldredge and Cracraft
(1980, *Phylogenetic Patterns and the Evolutionary Process*) wrote:
"the questions arise: to what extent are cladograms to be considered
actual representations of phylogeny? The concept of the cladogram has
been synonymous with 'phylogeny' in some of the prior literature. The
view taken here is that cladograms, in themselves, are not phylogenies,
but rather hypothesis about the pattern of nested evolutionary novelties.*
They differentiate clearly the *representation* from the *reality*. They
do not reify cladograms as being actual phylogenies. In this discussion,
we have to refer to the epistemological problem of the cognitive relation.
Knowledge is produced in a relation where both the subject and the object
interferes. The subject, as an active element in cognitive process,
produces a knowledge about the object which is an image, a representation
of the object as a material entity, but not a copy of it. The scientist
is a real existing man; they have political, ideological positions, they
have economical interests, they have, sometimes, a creed, or, who knows,
some form of metaphysical conjectures, and all of these properties,
qualities of a real man, will influence the scientific knowledge which
is produced. So, it seems, by the very properties of cognitive relation,
by the constraints of knowing the objects by being *in relation* to them,
that we cannot know the world how it really is. We have only images of the
world, which are true because they reflect the material existence of the
objects in the world, but which are, at the same time, not true, because
an image can be a deception, we cannot be sure that the real object is
like the image. Mirrors - says Borges - are like labyrinths; they deceive.
 We cannot reify our images of te world. A cladogram is always a
hypothesis about patterns in the evolutionary history, and never a way
of constructing generalizations, reifications, about this history.
But this is not really a problem, because cladograms, *as hypothesis*,
are very useful for the understanding of patterns and processes in
phylogenetical history. What do you think?
 I would like to discuss these themes. Gerson wrote, in September 27,
*the historical sciences (and the branches of natural history) don't
generalize the same way that the physical sciences do*. We know that
the methods of physical sciences were of great influence in the history
of the methods in all fields of knowledge. But we also know about
the methodological crisis in social and historical sciences. We have,
in Darwin-L, to discuss this. To what extent the Cartesian scientific
method is valid in the historical sciences? What are the possibilities
and limitations of Cartesian method?

     Charbel Nino El-Hani
  Institute of Biology/MsC in Education
 Federal University of Bahia, Salvador, Bahia, Brazil
     Charbel@BRUFBA

     Diogo Meyer
  Institute of Biosciences, University of Sao Paulo,
 Sao Paulo, Brazil (today in Stanford University)
     Diogo@lotka.stanford.edu

P.S.: this is an old discussion between Diogo and me. Maybe he disagrees
of some the views expressed here. He haven't read this modification of
a criticism of him about what I have written. Charbel.

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