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The Chicken or the Egg
By Tom Scharle
Posted September 20, 2004
There is a history of arguments which were used against
one natural explanation of origins: Epigenesis, the development
of the individual living thing. This history can shed light on
the use of the same arguments against another natural explanation
of origins: Evolution, which deals with populations of living
things.
There Is Nothing New Under The Sun
There are many sayings to remind us how rare it is to have
a truly original idea. It is often startling to read through
history and find that the latest fads are a repeat of something
from long ago.
This was my experience when reading a book by Edwin Tenney
Brewster,
Creation: A History of Non-Evolutionary Theories.
Brewster discussed what we can call "scientific theories of creation",
and one that got my attention involved the 18th century discussion
of how an individual living thing came into its mature form. Did it
develop from an unformed state or did it exist in some form
in its precursor?
When does this creation occur?
...If there is no epigenesis but only [the "rolling out" of pre-formed
organs], then there is no such thing as generation either. All
creatures that ever were, or are now, or ever shall be to the end of
time, must have been created at the beginning by the direct act of
God, as germs.
[Brewster: Creation, page 166.]
For those who are unfamiliar with the issues,
there is a summary Survey of the controversy
below. Briefly:
"Preformation",
the idea that there was no real development, was a dominant
scientific idea for about 200 years, centering on the 18th century.
The "other side" of the controversy was represented by
"Epigenesis".
Epigenesis caused some people discomfort, for it seemed
incompatible with concepts of society and creation. And it is
interesting to see how many of the arguments used in favor of
Preformation have been recirculated (possibly unawares) as
arguments against evolutionary biology. These arguments were not
always what we would call "scientific": They could be philosophical,
ethical, or theological.
The purpose of this essay is to look at a few of the issues
which were brought up regarding Preformation and Epigenesis. The particularly scientific arguments and experiments were
eventually resolved. But other objections persisted
beyond their original application: they kept the substance of the
objection and changed the thing objected to.
"Which came first, the chicken or the egg?" -- that old
question seemed to be a problem for traditional Epigenesis, and
might be asked about Evolution, today, by anti-Evolutionists.
Quite literally: How could a chicken come from something which is
not a chicken; and the early investigators (beginning with Aristotle)
examined chicken eggs at various stages of growth. But it can also
serve as a metaphor: Which came first, the objections or the
objectionable idea? Here there are a few of these objections:
Irreducible Complexity
Since the publication of Behe: Darwin's Black Box,
the expression "Irreducible Complexity" has received much notice within the
anti-evolutionary community. A biological system is said to be
Irreducibly Complex if it could not work as a system if a
significant part of it were missing, and thus, supposedly,
it could not develop in a gradual, evolutionary way.
Some 300 years ago, Nicolas Malebranche
argued that there could
not be an Epigenesis because of the interactions between the various
organs in a complex living thing. A heart could not develop, he
said, before there were veins to carry the blood, and the veins could
not be there before there was a heart, and so on for the various organs
of an animal.
The same argument against Epigenesis and for Preformation was
also used by Cotton Mather,
Charles Bonnet, and
Abraham Trembley. See the quotions about
Irreducible Complexity below.
A Cautionary Tale
Let us pause for a moment and reflect on what we can learn
from the history of the idea of Irreducible Complexity, as seen
through the eyes of the 18th century.
This could be repeated for other arguments from the era of
Preformation (in particular for the arguments which will be looked
at later) and perhaps also for arguments which, although as
a matter of historical accident did not arise then, are
current today.
I have chosen this argument because it is being used today as
an argument against Evolution. It is not merely of historical
interest. Perhaps history can shed light on the soundness of
the argument in general, and in particular on how much it
supports a different conclusion from its earlier use. Insofar
as we can use the word "creationism" to describe ideas before
the word was used, Preformation was a scientific theory of
creationism.
Next, because the argument, as used to argue against Epigenesis, was
at least as sound as its present use against Evolution.
Perhaps it was more sound, because it was not merely against Epigenesis,
it was for Preformation. (As distinguished from being
merely against Evolution, with it being left open as to what it
is for.) And it was part of a consilience of evidence for this
genuinely scientific theory, which included observational
examinations.
Finally, because this argument was used in its earlier form in the debate
about the origins of individuals, rather than the origins
of species, kinds, types, patterns, generalities or abstractions.
This shows that this distinction, between "origins of individuals"
and "origins of kinds", is not merely metaphysical hair-splitting,
but is a distinction which makes a difference in the real world.
This is not a "straw man". The argument was used by serious,
intelligent, informed people in support of a legitimate scientific
investigation. We can use this distinction as a tool to examine
other arguments, asking the question: "Is this an argument against
Evolution, or is it more properly an argument against Epigenesis?"
These further examples suggest that there is a pattern to this
history of arguments.
Original Sin
Many people are concerned that evolutionary biology has
troublesome conflicts with traditional Christian theology,
especially with the concept of Original Sin. It is interesting
that this particular theological problem has also been anticipated
in the Epigenesis:Preformation debate.
There are some scattered allusions in the Bible which have been
taken as support for the idea of pre-existence of the body in one's
ancestors (Genesis 25:23, and
Jeremiah 1:15 for existence in the
maternal body); but the one that has received the most attention,
as far as Original Sin and Preformation, was
Hebrews 7:10.
Jan Swammerdam made the explicit association
between Original Sin and Preformation, although hints
of it are given by James Ussher and back to
Augustine. Extended quotations about
Original Sin
are given below.
Voltaire's Dispute with Epigenesis
Although Voltaire was not a systematic
scientist and was certainly not a traditional Christian believer,
he did accept the idea of Preformation, in part because of his deistic
beliefs, and used the power of his rhetoric to argue against
Spontaneous Generation especially. It is interesting to see
that this person -- perhaps the epitome of the anti-church
deist of the 18th century -- argued vehemently for Preformation,
using several of the same arguments that feel comfortable to
modern religious anti-evolutionists.
The copious writings of Voltaire make for a handy source for a longer list
of further objections to Epigenesis. These objections may have been
used by others, and may have not all been original with him.
Here are a few of his themes:
One of the more famous quotations of Voltaire is "If God did
not exist, we would have to invent Him" "Épitre à l'auteur du livre des Trois imposteurs"-- meaning, for Voltaire,
that morality is possible only for those who believe in God.
Moreover, Voltaire often claimed that
Spontaneous Generation and Epigenesis led to atheism:
If animals were born without a germ, there would be no more cause
of generations; a man could just as easily be born of a lump of
earth as an eel from a bit of paste. This ridiculous system would
obviously lead others to atheism.
[Avertissement to Letters 5-8]
[my translation]
See also Voltaire's essay on "Atheism" in his
Philosophical Dictionary.
The analogy between a watch and a living thing, the watch being so
complicated that it requires a watchmaker, so too a living thing
requires a designer. In the 18th century, the issue was about each individual
living thing being a creature; in the 21st century the individuals have been
forgotten, and the issue is rather "kinds" of living things.
... no matter what some savants say nowadays, one can be a
very good philosopher and believe in God. The atheists never
replied to the difficulty that a clock proves a clock-maker.
[To Marquis Villevielle]
[my translation]
Later, in this same letter, he brings up a little calculation
of the small probability of getting the opening of Virgil's Aeneid by
throwing letters at random, and adds the comment that "Two Aeneids together
do not make a third."
The expression Spontaneous Generation naturally suggests
the thought that the living thing "just happens", and Voltaire, like
21st century anti-evolutionists, identifies anything other than
creation as being "chance".
Voltaire has a long essay in his Philosophical Dictionary defending
the concept of Final Causes. See "Final Causes"
Voltaire seems to have had a limited concept of what sciences
could investigate, rather similar to 21st century objections to
Evolution as not a "true science":
True physics consists then in the proper determination of all the
facts. We will know first causes when we are gods. It is given to
us to calculate, to weigh, to measure, to observe; this is natural
philosophy; almost all the rest is a chimera.
["Cartesianisme"]
[my translation]
Ever-Changing Terminology
When reading authors from the 18th century or thereabouts,
keep in mind that there can be a shift in the meaning of words
over time.
When they are talking about "design", they might mean one thing
while a 21st century writer means another. For one thing, remember that
in earlier days, the typical human designer would have been the
craftsman or artisan who would make objects individually,
whereas today, the designer is someone who draws up designs for
mass production or even for a system for producing designs.
The 18th-century problem that we are looking at is a problem about
how each individual living organism comes to be and whether it
was individually designed or grew on its own. The 21st-century
complaint about evolution is that it displaces not individual
creation, but wholesale design of species or kinds of living things.
When the 18th century philosopher contemplated the complexity of
an eye and couldn't imagine how an eye could arise by natural
processes apart from a designer, it was an eye that was being
talked about, not -- as is regularly the case today --
the eye. That is, each individual eye, one at a time, rather
than the overall pattern of all eyes.
Conclusion -- Is There Nothing New Under The Sun?
There are, of course, other arguments proposed today against
evolutionary biology. It is far beyond the scope of this essay
to cover those which are new, but perhaps we can suggest that an
interested reader could try this exercise: How many arguments
which are brought up against evolutionary biology might be
at least as appropriate as an argument against Epigenesis?
This suggests a minor research problem in the history of
thought: How many 21st century arguments against Evolution were
anticipated in the 18th century as arguments against Epigenesis?
Can an argument against Evolution be identified which has
no precursor in the anti-Epigenesis debate?
There is one major difference in the old
anti-Epigenesis arguments, though, and that is that there was a
positive alternative theory available -- Preformation offered
a description and explanation of what happened, and there were
experimental investigations proposed, and actually done, in
support of Preformation. Preformation was a genuine theory, and a
scientific theory.
This essay suggests some of the range of those who objected
to Epigenesis at least in part for theological or philosophical
reasons. And some of these objections have persisted, even though
the original issue has faded away, and was replaced by the new
issue of evolution.
In summary, then:
- There are the historical facts: A scientific theory, Preformation, and
the arguments which have been used to support that theory. This theory
has generally been discarded, but the arguments have recurred in arguing
about a different subject matter, Evolution.
- These historical facts suggest a pattern for the recurrence of
arguments.
- These historical facts illuminate the distinction between the origins
and development of the individual and of the kind.
- These historical facts raise doubts about whether the later
use of the arguments is more persuasive than the earlier.
Postscripts
- Additions and Clarifications
- A Survey of the Preformation:Epigenesis Controversy
For a book-length popular treatment, see
Correia: The Ovary of Eve
Short expositions of one phase of Voltaire's campaign against
Spontaneous Generation are in
Hellman: Voltaire versus Needham
Roe: Voltaire vs. Needham
How does the complexity of structures of each living
thing arise? There is a confusing complexity of different terms
used in the literature. As is far too common, people attempt to
coin new words to make fine distinctions, only to have the words
used in different ways by different authors. See comments about the
variety of expressions in Strick: Sparks of Life,
especially pages 11-12, 90-91, 237. I will restrict
this to just three technical terms, "Epigenesis", "Spontaneous
Generation", and "Preformation".
- Epigenesis
The first, ancient answer to the central question -- going back at least
as far as Aristotle -- is to accept the common-sense observation that
these complexities do develop from basically unformed predecessors,
for example, plants from seeds and egg-laying animals from eggs.
The modern-day equivalent of this is essentially developmental biology,
the study of how all of the varieties of cell-types and organs in the
adult come from a single precursor cell (the fertilized egg, for
example).
- Spontaneous Generation
Closely associated with Epigenesis is the idea that living things
can develop from foreign material -- as mistletoe grows on trees,
flies from rotten flesh, mice in rubbish-heaps, and, indeed,
butterflies (winged, six-legged insects) from caterpillars (non-flying,
many-legged "worms"). This, of course, is also an ancient belief, going
back at least as far as Aristotle. Today, in retrospect, we can recognize that
Epigenesis and Spontaneous Generation can be distinguished. But in the
18th century, they were treated as a package by all sides of the
dispute.
- Preformation
The new idea of the 17th century was that the basic structures of
each living thing already existed in their complexity in their precursors,
that is, the seed, eggs, or the newly-discovered spermatozoa. This is
"preformation". Preformation began to get notice in the 17th century
and seems to have been the dominant opinion of the 18th century.
An extension of preformation is "pre-existence": That not merely the
major organs exist in the precursor to the mature form, but that the
entire mature body actually exists, in a small form, in the precursor,
and that what we perceive as development is merely growing larger.
An extreme form of preformation held that, as the egg contained the
adult form, and the adult form contained eggs, there was a nesting, as
the common metaphor puts it, like Russian dolls; so that all generations
of humans were contained within the body of Eve. In partial defense of
this idea, which is a subject of ridicule today, remember that Newtonian
physics and infinitesimal calculus presumed that matter was infinitely
divisible and that there was no idea that there was a lower limit, imposed
by the size of cells, to the size of a living thing. Microscopes had
discovered an amazing variety of unsuspected complex small life. At this
point a quotation from Swift's "On Poetry" of 1733 is usually demanded:
So, Nat'ralists observe, a Flea
Hath smaller Fleas that on him prey,
And these have smaller yet to bite 'em,
And so proceed ad infinitum:
Today, the typical references one can find to Preformation tend
to be dismissive, even ridiculing it with the idea of a "little man"
inside the mother (or father). Today, so it goes, we all know better,
that there really is a process of development from a fertilized egg,
and all of those people must have been sorely deluded to contemplate
such a preposterous idea of an infinite sequence of "little men" inside
one another, back to Eve (or Adam), and forward all generations.
Keep in mind that very little was known about such basic facts about
the world of life, facts that we learn in elementary school, such as:
all life is composed of cells and all life is based on chemistry; the
mammalian egg had not yet been observed and microscopy was at a very
primitive stage compared with even late 19th-century practice.
And just to hint at the complexity of the intellectual currents of the
time, anything associated with Aristotle was in disfavor among many of
the scientists of this era.
The idea of Preformation faded away in the early 19th century, although
as late as the 1840s William Whewell could say
that "It has always had many adherents; and has been, perhaps, up to the
present time, the most current opinion on the subject of generation."
[Philosophy of the Inductive Sciences, volume 1,
page 295].
Spontaneous Generation gradually became dissociated from the "victorious"
Epigenesis and was eventually discredited.
- Some Clarifications and Disclaimers
This essay is not the place (and I do not claim to be the person) for
a history of biology during the Englightenment (roughly, that is, 18th
century European culture). Rather, we are trying to find lessons from
fragments of old debates for thinking about modern issues.
In particular, it would take us far astray to consider what the
supporters of Epigenesis had to say (and they were not silent).
Likewise, we are not concerned with what later theories of evolution
had to say: Although this essay dwells on the issues of the origins of individuals
and the origins of kinds -- what we can label "Ontogeny" and "Phylogeny"
-- the essay is based on the differences between these
concepts, not on any connection (such as the idea of "recapitulation",
which came to prominence in a later period).
It must be stressed that this essay is not a "Whiggish history" which
attempts to evaluate the past by present standards. But that does not
preclude the evaluation of the present by present standards, including
standards which are informed by our knowledge of the past.
- Selected Quotations
- Irreducible Complexity
An organized body contains an infinity of parts which mutually depend,
one on the other, according to particular ends, & which must all be
concurrently formed in order to act all together. Because it should
not be thought, as did Aristotle, that the heart is the first one
alive & the last dying. The heart cannot beat without the influence
of the animal spirits, which spread themselves in the heart without
the nerves, & the nerves draw their origin from the brain whence they
receive the spirits. Moreover, the heart cannot beat & push blood in
the arteries if they are not already made, as well as the veins which
bring it back. In a word, it is obvious that a machine cannot act that
is not completed, & that thus the heart cannot live alone.
[Malebranche De la recherche]
[Book VI. Part II. Chapter IV.; volume 3 pages 169-170]
[my translation]
[See Aristotle "On Youth" 3: 468b28]
The question is thus to know, if an Animal, before it is perceptible,
is already formed, if it has all its Organs, & if it has them since
the first moment of its existence; or, if, in this state of smallness,
the Organs are formed successively, & are not all formed & arranged,
in this harmony which is between them, when the Animal becomes
perceptible. In fact direct observations can be useful to
clarify this question, since the small Animal is imperceptible in the
circumstances in which it all is. But we can reflect on the observations
made on the small Animals, when they became perceptible, & when they
acquired considerable degrees of increase. We see whereas they form a
whole composed of a multitude of parts closely plain between them; &
that, to speak with the excellent Author, most properly to be used by us as
Guide in this research, "all these parts of an Animal have between them
such direct correspondences, so varied, so multiple, so close in
connection, so indissoluble, that they must always have coexisted. The
Arteries suppose the Veins: these & others suppose the Nerves; those the
Brain; this last the Heart; & all suppose a multitude of Bodies."
[Trembley Discours XVIII,volume I
pages 263-264]
[my translation]
[the "excellent Author" is cited is Bonnet,
volume 1, page 154] [see Wesley vol. 2, page 238]
There is nothing in the Animal Machine, but an inconceivable
number of branching and winding Canals, filled with Liquors
of different Natures, going a perpetual round, and no more capable
of producing the wonder Fabrick of another Animal, than a thing is
of making itself. There is besides in the Generation of an
Animal, a necessity that the Head, Heart, Nerves, Veins and
Arteries, be formed at the same time, which never can be done
by the motion of any Fluid, which way soever moved.
[Cotton Mather, Essay XXVI. "Of Insects"; reprint, page 154]
- Original Sin
Now, there is no doubt that God knew Jeremiah before He formed him in
the womb, for He says quite clearly, Before I formed you in the
womb, I knew you. But it is difficult, if not impossible, for our
limited understanding to know where God knew him before forming him.
Was it in some proximate causes, as in the case of Levi, who paid
tithes when he was in the loins of Abraham? Was it in Adam himself,
in whom the whole human race had its roots? And if in Adam, was it
when he had been formed from the slime, or was it when he had been
made in his causes in the works which God created simultaneously?
[Augustine, Book 6 Chapter 9
Paragraph 14, pages 187-188]
Secondly, that we all who are descended from Adam by naturall
generation, were in his loyns and a part of him when he fell, and so by
the law of propagation and generation sinned in him, and in him
deserved eternall condemnation; therefore as two Nations are said to
be in the womb of Rebekah, Gen.25.23 and Levi
to have paid tithes to Melchisedec in the loins of
Abraham, Heb.7.9,10. who was not born some hundred years
after, so is it here.
[Ussher, Head 9, "Of Originall and Actuall sinne
...", page 142]
Moreover, the reason is evident, how Levi, being yet in his father's
loins, paid tythes long before he was born: for he was in his
father's loins, when Melchisedek met Abraham. Lastly, even original
sin (in the opinion of a very learned man, to whom we have occasionally
communicated the mysteries of our experiments) may stand on this
principle as on a firm foundation, since all mankind have been laid
up originally in the loins of their first parents.
[Swammerdam, Part I Chapter III, page 16]
- Biblical Quotations
- Genesis 25:23 -
And the LORD said unto her, Two nations are in thy womb ...
[King James Version]
- Jeremiah 1:5 -
Before I formed thee in the belly I knew thee; and before thou camest
forth out of the womb I sanctified thee, and I ordained thee a prophet
unto the nations.
[King James Version]
- Sirach 18:1 (also known as Ecclesiasticus) -
He that liveth for ever Hath created all things in general.
[King James Version]
He that liueth for euer, created al thinges together.
[Douai Version of 1609, translated from the Vulgate]
- Hebrews 7:9-10 -
And as I may so say, Levi also, who receiveth tithes,
payed tithes in Abraham. For he was yet in the loins of his father,
when Melchisedec met him.
[King James Version]
- Primary Sources: People and their Writings
- St. Augustine of Hippo (354-430)
His notion of "rationes seminales" has been claimed
(and denied) as a precursor of the idea of evolution; perhaps it could
be claimed for Preformation. It seems that he relied in part on a
Latin (Vulgate) mistranslation of Sirach 18:1.
- The Literal Meaning of Genesis
translated and annotated by John Hammond Taylor
nos. 41-42
Ancient Christian Writers
New York: Newman Press, 1982
- Charles Bonnet (1720-1793)
- Nicolas Malebranche (1638-1715)
- Cotton Mather (1663-1728)
- Jan Swammerdam (1637-1680)
Dutch Reformed.
A brief biography is online at:
http://www.janswammerdam.net/
One of the earliest proponents of preformation. In 1668 he had a public
dissection of a caterpillar demonstrating the existence of a butterfly
inside a caterpillar. His "Bybel der Natuure, of Historie der Insecten"
in Dutch with Latin translation was posthumously published in 1737, and
the quotations here are from this English translation:
- The Book of Nature; or the History of Insects
London: C.G. Syfert, 1758
- Abraham Trembley (1710-1784)
Christian (unspecified denomination).
Of the following two volume work, he wrote, "It is to Young People
that I present this Work. I had begun with the intention to put it
solely in the hands of my children. It was to be only a summary of
verbal Instructions that I gave them." (page iij).
Best known today for his work on regeneration in hydra.
- Instructions d'un pere a ses enfans
sur la nature et sur la religion
Geneva: Chez Jean Samuel Cailler, 1775
- James Ussher (1581-1656)
- Voltaire (1694-1778)
Deist and famous opponent of
organized religion. Proponent of preformation and vigorous opponent of
epigenesis and spontaneous generation.
- "Cartesianisme"
Questions sur l'encyclopédie
Dictionnaire Philosophique Tome III, volume 53 of
Œuvres complètes de Voltaire avec des remarques et des notes
Paris: Baudouin Frères, 1825
- Letter to the Marquis de Villevielle,
26 August 1768
Voltaire: Correspondence vol. 21; vol. 70 of
Œuvres complètes de Voltaire avec des remarques et des notes
Paris: Baudoin Frères, 1831
- "Atheism"
volume 2, pages 104-128
Philosophical Dictionary
William F. Fleming, ed.
Paris & New York: E. R. DuMont, 1901
- "Final Causes"
volume 5, pages 75-89
Philosophical Dictionary
William F. Fleming, ed.
Paris & New York: E. R. DuMont, 1901
-
Épître à l'auteur du livre des Trois imposteurs
Online, with translation and brief comments, at:
http://humanities.uchicago.edu/homes/VSA/trois.imposteurs.html
- Questions sur les miracles
volume 61 (Facéties) pages 289-458
Œuvres complètes de Voltaire avec des remarques et des notes
Paris: Baudouin Frères, 1825
see especially
Avertissement, pages 353-354
Cinquième lettre, pages 354-356
Sixième lettre, pages 356-359
Septième lettre, pages 359-362
Huitième lettre, pages 362-367
- John Wesley (1703-1791)
The noted founder of the Methodist movement was a widely
educated man and promoted the study of sciences among his
followers.
- A survey of the wisdom of God in the creation;
or, A compendium of natural philosophy.
Containing an abridgment of that beautiful work,
The contemplation of nature. By Mr. Bonnet, of Geneva. ...
New York: N. Bangs and T. Mason, 1823.
- William Whewell (1794-1866)
- Secondary Sources
- Michael J. Behe
Darwin's Black Box: The Biochemical Challenge to Evolution
New York: The Free Press, 1996
- Edwin Tenney Brewster
Creation: A History of Non-Evolutionary Theories
Indianapolis: Bobbs-Merril, 1927
- Clara Pinto Correia
The Ovary of Eve: Egg and Sperm and Preformation
Chicago: University of Chicago Press, 1997
- Hal Hellman
"Voltaire versus Needham: The Generation Controversy"
Chapter 4, pages 63-79 in
Gread Feuds in Science: Ten of the Livliest Disputes Ever
New York: John Wiley & Sons, 1998
- Shirley A. Roe
"Voltaire vs. Needham: Atheism, Materialism and the Generation of Life"
Journal of the History of Ideas, volume 46 (1985) pages 65-87
reprinted in John W. Yolton, ed.
Philosophy, Religion and Science in the Seventeenth and Eighteenth Centuries
Rochester: University of Rochester Press, 1990
- James E. Strick
Sparks of Life: Darwinism and the Victorian Debates over Spontaneous Generation
Cambridge, Mass.:Harvard University Press, 2000
Copyright © 2004 Thomas W. Scharle All Rights Reserved.
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