Recapitulation Theories
and Man's Place in the Universe
Linda Simonetti Odhner
INTRODUCTION
Before I state my thesis, I'd better clarify what idea I'm
referring to with the word "recapitulation." Some of you are probably
familiar with the phrase "Ontogeny Recapitulates Phylogeny." Ontogeny
denotes the process of individual development: not merely the prenatal
period but the entire lifespan, beginning with conception and proceeding
through embryonic development, birth or hatching, infancy, metamorphosis
in some cases, maturity, and old age, and ending in death. The embryonic
and larval stages are usually emphasized because they represent the most
dramatic changes.
Phylogeny refers to the sequence of ancestral forms in a
creature's evolutionary history. It can also describe a branching family
tree of hypothetical relationships between various organisms--called a
"phy-logenetic tree."
Therefore ontogeny recapitulates phylogeny means that the sequence
of stages in a creature's development repeats in brief--or recapitulates--
the sequence of adult stages in its ancestry. Take, for example,
recapitulation in man (fig.1). From this figure you may gather that the
application of this principle in real life is not all plain sailing. The
facts leave room for great differences of opinion as to how true
recapitulation is; it has a way of going in and out of fashion according
to the intellectual climate of the times. In recent years recapitulation
has undergone a revival of interest after about 70 years of contemptuous
neglect.
Swedenborg's thought--including both his theological doctrines and
his philosophy of science--offers an illuminating perspective on
recapitulation. One doctrine in particular, which I'll call the doctrine
of spiritual recapitulation, has special relevance to the concept of
natural recapitulation. The more general doctrines of correspondence and
of the human form create a context for the relationship between these two
kinds of
Fig. 1
Adapted from Hamilton et al., Human Embryology, figs. 91, 120, 123, 124,
125; Keeton, Biological Science, fig. 22.56; Hickman, Integrated
Principles of Zoology, fig. 29-19; Ballard, Comparative Anatomy and
Embryology, back endpaper; Moody, Introduction to Evolution, figs. 4.9,
8.22.
recapitulation, and also shed light on its philosophical implications.
Recapitulation, seen in the light of these spiritual principles, may be
able to tell us something about our place in the universe, especially how
we relate to other living forms on the earth.
Swedenborg's work may have played a significant part in the origin
of recapitulation as a scientific principle. This origin took place when
science was still in the process of differentiating from religion and
philosophy and becoming an independent domain of knowledge. Swedenborg's
philosophical works made a valuable contribution to this differentiation,
and early recapitulation theories are a prime example of the need for it.
Before I plunge into particulars I'd like to say a few words about
the relationship between science and religion. While some describe
religion and science as overlapping domains, I regard them as
complementary domains with an intimate relationship, but no real
intersection. I don't believe we can derive philosophical or religious
principles from scientific facts alone, nor can we derive scientific
principles from the tenets of religion or philosophy. However, from a
specific religious point of view we can work out the religious and
philosophical implications of a scientific fact, and also elaborate and
clarify our religious perspective. But we get out of science only what we
bring to it.
In this presentation I want to contribute to a synthesis of
religion and science that preserves their distinctness. Instead of
deriving doctrine from science or science from doctrine, I see an
analogical connection between them which emphasizes that they deal with
different levels of knowledge.
In the following I will show how Swedenborg's doctrine of
spiritual recapitulation bears on natural recapitulation. Next I present a
history of the recapitulation concept and the different forms it took
through the years, in terms of both philosophy and science, and how
disagreements and refutations shaped it to fit the facts more closely. And
finally I'll look at the role recapitulation and its alternatives play in
human evolution.
Spiritual and Natural Recapitulation
In Swedenborg's final work, The True Christian Religion, Number
762 states: "In the Lord's sight the Church is seen as a single man, and
this larger man must pass through his stages of life like an individual."
This amounts to spiritual recapitulation--man in his spiritual life
repeats the stages of spiritual development attained by his human
ancestors. However, this is more complicated than it looks, for man's
spiritual growth is not linear but cyclical: a series of descents into the
natural, concrete things of life followed by ascents into spiritual
things.1
In a sense the Most Ancient Church--the infancy of the human
race--was the spiritual apex of human development, for its members loved
the Lord above all, perceived spiritual things directly, and communicated
openly with heaven.2 They occupy the highest heaven.3 The churches which
followed this first one represented successively lower spiritual states.
Yet this descent is necessary to bring about a new ascent and a new peak
in man's history. How this would have been achieved without the perversion
of the Fall, no one can answer with certainty.
The succession of states in an individual person's growth mirrors
this spiritual descent in human history. Celestial angels surround an
infant until his growing self-will tempers his total openness and
innocence, when spiritual angels take their place.4 And so it goes; and
many later cycles in his life will follow the same pattern.
In figure 2, I've placed the quotation concerning spiritual
recapitulation in a context which shows how it might relate to natural
recapitulation. The table shows four processes, two spiritual and two
natural, two general and two individual. Three of these are are explicitly
related to each other in Swedenborg's theological writings as human
processes. The quotation on spiritual recapitulation links the two
spiritual processes of individual regeneration and racial development. In
addition, Swedenborg makes a strong connection between the natural process
of human gestation and the spiritual process of human regeneration. Not
only is there a "likeness and analogy," as stated, between the two, but an
actual correspondence--a cause-and-effect relationship which prevails
throughout the created universe. The complete correspondence between the
human soul and body is just one instance of this universal connection
between spirit and matter.5 Cycles of spiritual growth have their
corres-pondential basis in natural cycles of growth and reproduction. Now,
since individual regeneration has its own correspondence in human
gestation, the universal law of correspondence implies a natural event
which corresponds to the spiritual growth of the Grand Man, the form of
heaven as a whole--in other words, a natural gestation process for the
whole human species. That's where evolution comes in. I think of the
descent by modification of those organisms leading to man as humanity's
physical gestation. And so did those who supported the "biogenetic law" of
the previous century--recapitulation.
Figure 2
While an adherence to Swedenborg's theological doctrines suggests
some kind of parallel between ontogeny and phylogeny, this parallel could
take some form other than recapitulation. Keep in mind that it cannot be a
correspondence in the Swedenborgian sense, because correspondence operates
only between different planes of creation--it's a vertical
interaction--and both ontogeny and phylogeny take place on the physical
plane.
I'm not going to tackle the evolution controversy in this paper.
But it may interest you to know that you don't have to subscribe to the
evolutionary point of view to accept recapitulation. And that leads me to
the historical part of my presentation.
History of Recapitulation
I have three purposes in summarizing the history of
recapitulation:
1. To arrive at a fuller understanding of recapitulation itself, and
the attitudes that underlie its various forms, through a study of its
development--its ontogeny, if you will.
2. To discover how various versions of recapitulation appear in terms
of the Swedenborgian doctrines of spiritual recapitulation,
correspondence, and the human form.
3. To determine Swedenborg's role--a small one, but not
inconsiderable--in the history of recapitulation.
To help you keep your bearings in the ensuing horde of eminent
figures in the history of science, I'm giving you a List of Important
Characters in chronological order of birth (fig.3).
Aristotle (384-322 B.C.), Greek philosopher
Lamarck, Jean (1744-1829), French naturalist
Cuvier, Georges (1769-1832), French anatomist
Oken, Lorenz (1779-1851), German naturalist
Meckel, Johann (1781-?), German natualist
Baer, Karl Ernst von (1792-1876), German-Russian embryologist
Darwin, Charles (1809-1882), Englist naturalist
Haeckel, Ernst (1834-1919), German naturalist
Figure 3
In all scientific and historical matters concerning
recapitulation, my primary source is Stephen Jay Gould's excellent book,
Ontogeny and Phylogeny. When I mention Gould I'm referring to this book.
The analogy between individual development and the progression
from lower to higher animals has been around at least since Aristotle. The
"Scala Naturae," or ladder of nature, is not an evolutionary progression,
but a fixed and static one. All members of the animal kingdom are arranged
on a single, linear staircase which ascends from the lowest species
through the higher ones to its human apex. Aristotle compared this Scale
of Being (as it is also called) with embryonic stages to confirm his
assertion that development unfolds from an unorganized, undifferen-tiated
beginning--the epigenetic view of embryology.6 Aristotle used this
comparison only as an analogy--not as a scientific principle. To encounter
a scientific version of recapitulation we must move forward over two
thousand years to the end of the 18th century, shortly after Swedenborg's
death.
Swedenborg and Naturphilosophie
The matrix in which the scientific principle of recapitulation
emerged was a philosophical movement going by the German name of
Naturphilosophie. In the interest of ready understanding I'll refer to
those who created and followed this school of thought as
Nature-philosophers. The basic ideas which formed Naturphilosophie closely
resemble some of Swedenborg's philosophical and theological thought, and
there is some evidence that he may have exercised an indirect influence on
its formation. Most generally, of two opposing philosophical trends in the
18th century, Swedenborg followed the one which led to Naturphilosophie. I
quote from Erik Nordenskjold's History of Biology:
Parallel with the [materialistic] philosophy of the enlightenment...
there developed another, entirely contrasted, conception of nature,
... which, possessing in Stahl, Swedenborg, and Caspar Friedrich Wolff
its scientifically most important representatives, appears throughout
the eighteenth century in various forms; a view of life which sees in
natural phenomena an expression for the operations of spiritual
powers, whereas, according to its tenets, the mechanical explanation
of nature admits of only a superficial observation of what takes
place, without any insight into that inherent connexion in existence
which the spiritual powers imply.7
More specifically, Goethe was an individual who absorbed
Swedenborg's work and, in turn, profoundly influenced Naturphilosophie. He
believed that all natural science was based on comparison, and that an
"ideal type" (shades of Plato?) existed with which all animal forms could
be compared. Rejecting materialism, he regarded the spiritual element as
essential in understanding science.8
Some of the ideas of Lorenz Oken, one of Naturphilosophie's most
important representatives, are described by Nordenskjold in these terms:
We find in [Oken's ideas] a great deal of ancient mysticism,
such as the mysticism of numbers--recurring groups of three and four--
the comparing of the animal kingdom to a great body, reminiscent of
Swedenborg's speculations... .9
Now all this may be interesting, but it's pretty flimsy evidence;
and keep in mind that this is not a definitive study, because in no case
did I consult the original source in question. In any case, I believe that
the connection between Swedenborg's theological doctrines and the idea of
recapitulation is more significant than the degree of actual influence
involved. Regardless of the influence question, striking similarities
exist between Swedenborg's work and Naturphilosophie.
Gould summarizes the basic beliefs of Naturphilosophie as follows:
"1. An uncompromising developmentalism." Not any one form, but the
movement from initial chaos to final order in man, from lower to
higher, is the "irreducible property of nature."10 Gould emphasizes
that this does not require a belief in evolution; physical continuity
is not necessary where spiritual continuity is present.
"2. A belief in the unity of nature and its laws. Man is the highest
configuration of matter on earth, but we are indissolubly linked to
all objects as the goal toward which they strive."11 These statements,
the last one in particular, strongly recall Swedenborg's, "Everything
in nature has relation to the human form,"12 and also, "The uses of
all created things ascend by degrees from ultimates to man, and
through man to God the Creator from whom all things are."13
Now, the form which recapitulation originally took depended not
only on its philosophical milieu, but also on two other things: the state
of embryology at the time, and the perception of how different forms of
life could be organized to create a meaningful pattern. I'll start with
embryology, and Swedenborg fits in here too.
Swedenborg and Embryology
Deep thinkers on the subject of embryology--and Swedenborg is no
exception--tended to avoid the extreme forms of both epigeneticism and
preformationism. Most preformationists didn't really believe that a tiny,
fully formed homunculus sat curled up in every human sperm head. Most
epigeneticists didn't believe that the fertilized egg was a completely
unorganized mass whose development was directed solely from without--or
above. Those who favored epigenesis pointed to the visible evidence of
gradual formation from apparent initial chaos. Those who espoused
preformation pointed to the equally visible evidence of developmental
consistency, and concluded that the egg had to contain the essence of what
it would become. Both positions were equally valid.14 At the time
Naturphilosophie began to flourish, the pendulum was swinging toward an
emphasis on epigenesis.
Swedenborg was fascinated by embryology and studied others'
observations on the subject. He believed in the soul as a spiritual entity
directing natural development, and inferred the soul's mode of operation
from scientific observation. He noted that in the egg there was "no type
of the future body,"15 and concluded that there must be a spiritual
"formative substance or force"16 guiding development, and what's more,
that the egg reflects this force in an order that is invisible yet
physically present: "for what before appeared to the eye a blank
undigested mass, is now seen to involve the most perfect order and
accurate discrimination."17 With these words Swedenborg encompassed both
sides of the argument. He did not treat the postulation of spiritual
forces as a scientific copout; he wasn't letting us off the hook in terms
of scientific observation and explanation.
The Animal Kingdom
Now we turn to the puzzle of variety in animal forms. The
domination in men's minds of that ancient linear hierarchy, the Scale of
Being, began to weaken as they came to terms with the staggering diversity
among different forms of life. It was getting harder to make everybody
stay in line. The branched model of animal classification began to take
over under the influence of Linnaeus and Cuvier. The Nature-philosophers
stuck with the Scale of Being, and considered the philosophical
significance (usually in recapitulatory terms) of animal traits. But
Cuvier rejected both Naturphilosophie and the Scale of Being, seeing the
significance of anatomical facts purely in terms of function. A
Nature-philosopher would see a clam as symbolizing a stage of human
development; Cuvier would assert that clams have absolutely nothing to do
with human development, since they belong to a different branch of the
animal kingdom.18 The evolutionary question naturally follows here, but
I'll postpone it until after I've described the Nature-philosophical brand
of recapitulation, which got along nicely without the benefit of evolution
for many years. After that we can see how evolution fitted in.
The Meckel-Serres Law
The Nature-philosophers were always making analogies--it was their
favorite pastime--and attaching great significance to them. This grew
naturally out of their basic principle: "The laws of nature operate in the
same way upon all processes and all objects."19 Any similarity seen or
imagined between different phenomena might become the basis for a new law
affirming nature's unity. Recapitulation was actually one of the most
sensible and factually based of these many parallels. In Naturphilosophie,
recapitulation fits into a larger scheme funneling the whole of nature
into the linear Scale of Being; beginning with various minerals and
progressing through plants and animals, "the form of organization
ascend[s]," culminating "in the form of a man."20
Leading Nature-philosopher Lorenz Oken endorsed recapitulation
wholeheartedly. He saw it in relatively crude terms as the simple addition
of organs and powers. Only man has the full complement of organs; all
other animals lack one or more. If "the stages of human ontogeny...
represent the completed forms of lower organisms," then, as Gould
paraphrases Oken, "what are the lower animals but a series of human
abortions?"21 And quoting Oken directly, "The animal kingdom is only a
dismemberment of the highest animal, i.e. of man."22 Seeing the animal
kingdom in these terms may be revolting, but it does follow logically from
Oken's prior assumptions.
Nature-philosophical allegiance to the relentlessly linear Scale
of Being is another aspect of the same tendency to do symbolic violence to
nature. In Oken's scheme, polyps, clams, and snails rub shoulders (so to
speak) with worms, flies and fish in flagrant disregard of their great
differences. This constriction of the branching tree of animal diversity
into a telephone pole of "human dismemberments" illustrates the way the
Naturephilosophers throttled nature into what they judged was the proper
shape to demonstrate man's supremacy in nature.
This system led to great absurdities when applied to human
development. If a "clam stage" in the human embryo sounds silly, the idea
that the human newborn represents a "bird stage," due to a lack of teeth,
doesn't improve matters. (Gould cautions us, "It is important to
understand what Oken means by these statements, lest he be dismissed as a
madman.")23 The connection is not one of actual identity or even
appearance; the embryo merely passes through stages symbolized by these
various creatures, as it adds the organs which represent the essential
nature of each. This sort of thing lifts recapitulation right out of the
realm of science.
Naturphilosophie and recapitulation are both fascinating and
useful to contemplate. It's just this particular combination of the two
that irritates me. I'm being hard on Oken, scorning his version of
recapitulation as the most disgusting ever to come down the pike, but I'm
doing it for the purpose of contrast.
The Nature-philosophical principle that all animals can be viewed
as stages in a progression leading to man superficially resembles
Swedenborg's doctrine that all living creatures are animated by a striving
toward the human form.24 The essential difference between the two ideas
rests, I believe, in the definition of "human." When comparing the human
form with animal forms, the Nature-philosophers naturally saw it in
physical terms. But this inevitably led to seeing the animal kingdom as
(to use still another metaphor of the time) "Man disintegrated."25
But according to Swedenborg's doctrine of the human form, our
humanity does not consist in our upright posture, our fingers or toes, our
warm blood, our way of reproducing, our facial features, or even our large
brains--none of which are outstandingly unique in the animal kingdom. None
of these things in themselves makes us human; they only make our humanity
possible. The human form, according to Sweden-borg, consists simply in
love and wisdom united in use.26 We human beings reflect this form in our
twin faculties of liberty and rationality-- that is, free will and the
ability to see what is true. These two capacities together enable us to
make wise choices and carry them out in our lives, and that is what makes
us uniquely human. The human form--love and wisdom united in use--is
universally present in creation. Most created things express this
unconsciously, but they all express it completely, in different forms and
in varying scales. This way of looking at the human form enables us to see
whole--not mutilated--images of it in all aspects of creation. We can
avoid the absurdity and the arrogance of thinking that other creatures
would be better if they were more like us, when they really perform their
own uses most perfectly as they are.
Keeping all this in mind, we can return to our history of
recapitulation. Johann Meckel's version of it was a refinement of and
improvement on Oken's. Meckel is considered the foremost spokesman for the
Nature-philosophical version of recapitulation, which in this century
acquired the name "Meckel-Serres Law" to distinguish it from Haeckel's
later and more famous "biogenetic law."27
Instead of seeing nature's developmental tendency in terms of the
simple addition of organs and powers, Meckel thought in terms of
"coordination and specialization; simple animals have many similar but
poorly coordinated parts; advanced creatures have highly distinct and
specialized organs that function together in an integrated body."28
Biological progress takes the form of "the reduction of many identical
parts to fewer, more specialized, and more coordinated organs."29 This
view of life's ascent can reflect Swedenborg's assertion that "a one
formed of many is never constituted of single things which are... exactly
alike; but of various things harmoniously conjoined."30
The other man for whom the Meckel-Serres Law was named, Etienne
Serres, belonged to the French transcendental morphologists, who shared
most of their basic assumptions with Naturphilosophie. The
transcendentalists believed in the Scale of Being and a single structural
plan to which the whole animal kingdom conformed. Serres admitted the
great diversity in adult forms as pointed out by Cuvier, but countered
this objection by pointing out the great similarities between vertebrate
embryos and invertebrate adults--that is, by invoking recapitulation.31
The most important thing to stress about the Meckel-Serres Law,
especially in contrast with the biogenetic law, is that it invokes no
direct causal connection on the physical plane between the ascents of
embryonic stages and adult forms. The parallel between the two arises
solely from their common origin in the spiritual law of universal striving
toward man, which finds a congruent expression in both processes. Figure 4
shows the structure of the Meckel-Serres Law: individual development is
continuous, the Scale of Being discrete, and their connection only on the
spiritual level.
Figure 4
Now we come to a man who achieved an unusual feat--he followed
Naturphilosophie but didn't accept recapitulation. This man was the
embryologist Karl Ernst von Baer, who may have done more for
recapitulation by his refutation of it than its most ardent champions by
their support. He saw all development unified by a single tendency, as the
recapitulationists did, but in his view all organisms tended toward
increasing differentiation from each other. In his words, "The development
of the individual is the history of growing individuality in every
respect."32 His opinion that there are several basic types of animal
agrees with Cuvier's interpretation of comparative anatomy, and he
maintains that these various types have no developmental stages in common
with each other. He emphasizes, "The vertebrate embryo is, at the
beginning, already a vertebrate; at no time is it identical with an
invertebrate animal," and goes on to say, "... in their development, the
embryos of vertebrates pass through no [known] adult stage of another
animal."33 Thus, animals of the same type resemble each other more as
embryos than as adults; but this is not recapitulation. Von Baer asserts
that development follows a diverging pattern, while recapitulation is a
linear phenomenon.
Now, several of the points which von Baer brings up in his
critique of recapitulation might be considered to be merely matters of
differing emphasis. After all, Oken and Meckel never claimed that any
vertebrate embryo is identical with any invertebrate adult. The issue of
divergent development is more of a problem; recapitulation requires that
changes in ontogeny be tacked onto the end of an existing pattern of
development, while von Baer asserts that the more two adult animals
differ, the earlier their respective ontogenies will diverge from each
other.34 And Von Baer's rejection of the Scale of Being is unequivocal. It
is impossible to fit all the members of the animal kingdom into a single
hierarchy. Since the Meckel-Serres Law was based on the Scale of Being it
could not be reconciled with von Baer's laws.
But evolution transformed recapitulation to an amazing extent, and
one result was to make recapitulation much more difficult to distinguish
from von Baer's point of view. Let's look at how evolution came to be
integrated with recapitulation.
The Biogenetic Law
Considering how long evolution and recapitulation were moving in
the same intellectual circles, they were a long time finding each other.
In his book Darwin's Century, Loren Eisely makes the point that, although
evolution was "in the air" in the 18th century, it took a long time to
enter the mainstream of biological thought, because in the process it had
to displace the belief in special creation and the fixity of species which
followed from a literal interpretation of the Bible.35 It is worth noting
that Swedenborg escaped this bondage to the literal sense of the Bible.
His scheme of each species of animal arising from a species of plant, in
The Worship and Love of God, while not evolutionary in the modern sense,
was a definite step away from special creation.36
Eisely also draws our attention to one of the reasons why
evolution began to make headway when it did: the epigenetic view of
development. As he puts it, "... to accept development, an emergence by
degrees, in the case of the single individual makes it possible to accept
with greater equanimity the conception that a species itself may have come
into existence by some more extended process of phylogenetic change."37
Attitudes toward the two processes of ontogeny and Phylogeny affected each
other because of the analogy that naturally crops up between them.
Lamarck's version of evolution (as far as I can find out) was
never linked with recapitulation, though it bore the marks of a
Nature-philosophical slant, and in fact incorporated the Scale of Being in
its structure. Why didn't the recapitulationists seize on it eagerly?
Perhaps Naturphilosophie simply wasn't ready for evolution. It wasn't
until after the publication of Darwin's On the Origin of Species that
evolution was finally married to recapitulation and gave it a new form.
The man whose name is associated more than any other with the new,
evolutionary version of recapitulation was Ernst Haeckel. Although, as
Gould points out, many people "rediscovered" recapitulation after Darwin,
Haeckel was the most conspicuous.38 He considered it the unifying
principle of biology, calling it the "biogenetic law." He coined the words
"ontogeny" and "phylogeny" (among many others), and originated the phrase
"ontogeny recapitulates phylogeny." It is his formulation of
recapitulation that I outlined at the beginning of this paper.
Evolution freed recapitulation from its uncomfortable fusion with
the now-outdated Scale of Being. It applied only to directly ancestral
forms on a branching family tree (fig. 5), and as a result, embryology
became a source of information about evolutionary lineages which
supplemented the fossil record.
Figure 5
The biogenetic law was much more of a scientific principle than
the Meckel-Serres Law could ever be, for it required a direct causal link
between ontogeny and phylogeny. Haeckel said, "Phylogeny is the mechanical
cause of ontogeny," and as far as I can see, you could just as well say it
the other way around; for while any current ontogeny is caused by the
phylogenetic series which leads up to it, each new form in that
phylogenetic series arises from a new increment in ontogeny. It puts me in
mind of the chicken-or-the-egg dilemma. In any case, it brings up a
question that can no longer be ignored: How are ontogeny and Phylogeny
causally related? To put it another way, how is hereditary information
passed on? Although speculation was rife, nobody really knew; so
recapitulation could not be proved or disproved on the basis of the laws
of inheritance. Instead, hereditary laws were deduced from the presumed
fact of recapitulation.39
Now let's get back to von Baer's laws. According to the biogenetic
law, recapitulation follows the branching pattern of evolutionary
lineages. In this case, any two species living at the same time, since
they display a fraternal rather than ancestral relationship, would show
divergent development. Their divergent phylogeny would be reflected in
divergent ontogeny. This result follows both from the biogenetic law and
von Baer's laws. Only when one form is directly ancestral to another are
the two points of view incompatible--recapitulation would predict
identical ontogeny until the end, while von Baer's laws would predict an
earlier divergence. However, it is usually impossible to make a direct
comparison between the ontogeny of an ancestral form and its evolutionary
descendant.
We can search for ancestral forms in the fossil record, of course.
We may come up with a nice string of fossil horses or hominids, and assume
they represent a single, direct line of descent. However, every new bit of
knowledge we acquire makes the phylogenetic picture more complex.
According to the Scale of Being, the organization of the animal kingdom
looks like this (fig. 6a): a straight line. According to Cuvier and von
Baer, it's a tree with four major branches, and Darwin followed this basic
scheme in his theory of evolution (fig. 6b). As more forms of life come to
light and the scheme of classification becomes more detailed, the tree
acquires more branches and twigs; and these days, to give an accurate idea
of the involved intricacy of even a fraction of all the lines of descent
would require a picture like this (fig. 7): a dense and tangled bush
bristling with little offshoots everywhere. Current theory predicts that
the majority of species, both living and extinct, never give rise to major
evolutionary lines. Therefore, given a series of fossil animals, even
closely related ones, the odds are against their being in a direct line of
descent. Thus it may be even harder in practice than in theory to
distinguish between von Baer's laws and recapitulation.
Figure 6
In fact, there is a considerable difference of opinion as to just
how much difference there is between them. It strikes me that the two
points of view are only mutually exclusive if they are generalized as
universal principles--there's an area of possible overlap between them.
Gould is absolutely adamant in his opinion that they are fundamentally
incompatible, and have been confused far too much over the years;40 Ernst
Mayr, in his recent book The Growth of Biological Thought, asserts exactly
the opposite--that too much has been made of their differences and they're
not really as different as people think.41 Going for a third opinion to
Nordenskjold, we find that he supports the idea of a clear-cut distinction
between recapitulation and von Baer.42 I don't have a definitive answer to
this problem--frankly, it has me stumped for the moment.
The facts of embryology are numerous and complex, and how you see
them depends on your point of view. Glaring exceptions exist to both von
Baer's laws and Haeckel's biogenetic law, although both viewpoints find
striking support in individual cases. Haeckel had to allow for scores of
exceptions to his law. One concession to facts which strengthened the
biogenetic law was the realization that an organism didn't recapitulate
its ancestors as a whole nearly as faithfully as in its individual organs
and systems. The timing in development of any component was often
dissociated from the others.43
I often think it would be nice if Haeckel had been right. The idea
is so elegant and so evocative of Swedenborgian doctrine--a gestation
process for the human race having an exact parallel with individual human
development. But despite all the examples supporting recapitulation, and
despite the exceptions the biogenetic law generously allowed for,
recapitulation as a universal principle couldn't stand up in the face of
genuine knowledge about how heredity works. As it grew clear that heredity
consists of discrete, coded instructions with their own hierarchy of
operation--some genes regulating the rates at which others governed
various processes--the idea that only the end of ontogeny could be
affected by genetic mutations became untenable.44 Any stage in ontogeny
was fair game for the effect of mutations. And any change occurring early
in ontogeny was likely to affect all subsequent stages as well. Thus, von
Baer's laws survived the emergence of a true science of genetics better
than Haeckel's law of universal recapitulation did. Recapitulation was
reduced to just one of several modes of evolution.45 And yet to those who
supported recapitulation it still seemed a fairly pervasive phenomenon.
Figure 7
To shed some light on why recapitulation may appear more
widespread than it actually is, I turn to von Baer. I present this lengthy
quotation in full as cited by Gould, not only because it's delightful, but
also because it illustrates some important points about how we see the
human form in its natural context. In his critique of recapitulation, von
Baer says:
Let us only imagine that birds had studied their own development
and that it was they in turn who investigated the structure of the adult
mammal and of man. Wouldn't their physiological textbooks teach the
following? "Those four-and two-legged animals bear many resemblances to
embryos, for their cranial bones are separated, and they have no beak,
just as we do in the first five or six days of incubation; their
extremities are all very much alike, as ours are for about the same
period; there is not a single true feather on their body, rather only thin
feather-shafts, so that we, as fledglings in the nest, are more advanced
than they shall ever be.... And these mammals that cannot find their own
food for such a long time after birth, that can never rise freely from the
earth, want to consider themselves more highly organized than we?"46
First of all, by putting himself in a bird's place, von Baer is
seeing the human form in creation in a far more broadening and universal
way than the strait-laced Scale of Being allows--or even, and I say this
with some regret, than the biogenetic law allows. He is not measuring the
rest of nature by man and finding it wanting. Instead he discovers how
essential human traits, which transcend physical form, might be expressed
in birds. Birds who write biology textbooks must be human, right? In this
context he brings up important points about our own perspective.
First, in judging the relative degree of advancement of various
animal forms, we tend to think in terms of our own particular
specializations, naturally considering them the most important and
significant. Other creatures are inevitably less advanced in the
specializations we specialize in, so in a way, recapitulation is in the
eye of the beholder.
A related point is that we see the differences between ourselves
and our near relatives more clearly than the differences among more remote
members of the animal kingdom. That is, we're more aware of, and more
familiar with, the details of our own neck of the taxonomic woods, with
the result that we find more significance in them too. This bias may
prevent us from appreciating the full diversity of life, as happened with
those who lumped most invertebrate species into a category called "worms"
and then forgot about them.47 Cuvier, who thought these "worms" merited a
second look and considerably more sorting out, avoided the "human" bias by
beginning his studies of comparative anatomy with marine animals such as
fish, molluscs and crustaceans.48
A full appreciation of the diversity of earthly life forms may
sharpen our awareness of the far greater variety of human affections among
men. No two people are exactly alike, and their different loves make up a
harmonious whole in heaven, for all of heaven takes the form of a single
man, as Swedenborg tells us.49
In a similar way the uses of different animals and plants combine
to form food webs and whole ecosystems in wonderful ways. The Scale of
Being is obviously a simplistic way of viewing these intricate
interactions, and so, less obviously, is the biogenetic law--still too
neat and tidy, still with too much emphasis on hierarchy. I would hate to
have to give it up completely, but I might loosen my hold on it if I could
find something equally suggestive of spiritual principles to take its
place.
If recapitulation is merely one mode of evolution among several,
as Gould asserts,50 then its opposite--paedomorphosis--should occur
frequently too. Paedomorphosis is the appearance of juvenile features in
the adult, which implies that the previous adult features are lopped off
the end of ontogeny into oblivion. It results from retardation of
development relative to the timing of maturity. In the days when the
biogenetic law held sway, paedomorphosis was dismissed as a degenerate
exception to the prevailing drive toward recapitulation. But in this
century paedomorphosis began to be recognized as an important mechanism of
evolution, just as creative, in some cases, as recapitulation.
Paedomorphosis possesses special interest as a significant factor in human
evolution.
Recapitulation and Paedomorphosis in Human Evolution
Let's start with some examples of recapitulation in human
evolution, and then we'll get to paedomorphosis. I doubt that any
similarities between ontogeny and phylogeny stand unchallenged as examples
of "real" recapitulation. Nevertheless, some of the parallels, especially
those
Figure 8
Adapted from Moody, op. tit., fig. 4.16; Ballard, op. tit., figs.
25-5,25-7,25-11; Hamilton et al, op. tit., figs. 159, 168.
which involve single organs and systems, are striking. The mammalian heart
recalls its vertebrate ancestors with respect to its division into right
and left halves (fig. 8).
The hearts of fish, amphibians, reptiles, and mammals show
progressively more complete septation as their double circulations grow
more efficient; the human heart follows this sequence, and while it is
essentially complete early in development, the last hole closes only after
birth, when air-breathing begins.
The human embryo shows other traits which hint at its origins,
among them a tail and a notochord which later disappear, and eyes which
begin on the sides of its head before converging toward the front. The
human brain, like the heart, recalls the vertebrate sequence of increasing
size and relative importance of the cerebral hemispheres (fig. 9). It
begins as a simple tube which then folds and buckles, and the forebrain
gradually grows over the rest of the tube to become the cerebrum. In this
respect the brain does exhibit recapitulation. But it achieves its large
size by means of a retardation in the timing of growth rates. Primate
brains are characterized by an initially steep growth curve, which levels
off at about the time of birth. Human brains follow a curve of about the
same shape, but the leveling off occurs much later, at about two years of
age, which results in a large size in both absolute and relative terms.51
Since a large brain relative to body size is a juvenile characteristic in
primates--in fact, in mammals generally--man's relative largeness of brain
is a paedomorphic trait. The human brain achieves the interesting feat of
being recapitulatory and paedomorphic at the same time.
It may be possible to make the following generalization: those
traits in man which show recapitulation do so with respect to other
vertebrate classes, while his paedomorphic traits refer to mammal and
primate characteristics. In other words, the general paedomorphic trend is
a relatively late phenomenon in human evolution. This is probably an
oversimplification, as many generatlizations are, but possibly useful
nonetheless.
Man's relatively large head and brain may be his most striking and
significant paedomorphic feature, but we can add others to the list, all
more or less related in terms of form and function. Man's flat face which
lacks a projecting muzzle, his small, late-erupting teeth in a small jaw,
his lack of a cranial ridge for attachment of the massive jaw muscles
which he also lacks, are all paedomorphic traits, and we're not even down
to the
Figure 9
Adapted from Hamilton et al., op. tit., figs. 359-362; Ballard, op.
tit., figs. 18-1, 18-9; Keeton, op. tit., fig. 10.44
neck yet. The attachment of tdenborg and She spine directly under the
skull, instead of at the back, allowing for man's upright posture, is also
paedomorphic-- and at the other end, his unrotated, unopposable big toe,
which makes walking easier.52 The list could go on.
All these things play a part in making man what he is in their own right,
but they also form part of a larger, more comprehensive picture of a
general slowing of the biological clock. An extended childhood forms part
of an extended life span in which many childish traits are never lost.53
From a Swedenborgian point of view, this has spiritual implications. Man
is designed by the Lord not only for a long life in this world, but also
for an eternal life in heaven--a life in which he can continue to make
free choices. Although each choice he makes in life eliminates certain
options, his life is never as circumscribed as that of an adult animal; he
needs to preserve the flexibility, the adaptability, the potential for
change, and the capacity for learning, of childhood.
Human paedomorphosis gains an added significance in relation to human
recapitulation. I suggested above that paedomorphosis followed
recapitulation in human evolution. If this is true it can remind us that
human growth returns to its origin over and over again. Descent into uses
and ascent into loves follow each other without end. As a child grows up
and increases in mastery of this world, his spiritual state descends.
Paedomorphosis in human evolution may illustrate the necessary return to
innocence in human regeneration. Since it involves a reduction in physical
strength and a childish appearance, human paedomorphosis may look like a
backward step in evolution, but it's really a step forward--just as
attaining the innocence of wisdom is a step forward in spiritual growth.
In both cases the traits which appear youthful on the surface veil a
deeper maturity of development.
This view of matters may represent just as severe a distortion of science
as a slavish allegiance to recapitulation. But perhaps it too is a step
forward, just as the biogenetic law was an advance from the Meckel-Serres
Law and the Scale of Being. A preconceived idea of how the facts of
science should support our philosophical point of view can lead to a
distortion of those facts; but coming to terms with the ways they
frustrate our expectations might bring us new depth of understanding and
insight in all areas of thought. It is not only the history of science
which suggests this conclusion; the same message emerges both from
Swedenborg's theological doctrines and from his example as a scientific
philosopher.
NOTES
1 Emanuel Swedenborg, Divine Love and Wisdom, nos. 170, 172, 316.
2 Swedenborg, Arcana Coelestia, nos. 784, 1121, 4448.
3 Arcana Coelestia, no. 1115 .
4 Ibid., no. 5342:2.
5 Ibid., no. 3619; Swedenborg, Heaven and Hell, no. 89.
6 Stephen Jay Gould, Ontogeny and Phylogeny (Cambridge, Mass.: Harvard
Univ. Press, 1977), p. 15.
7 Erik Nordenskjold, The History of Biology (New York: Tudor
Publishing Co., 1928), p. 269.
8 Ibid., p. 281.
9 Ibid., p. 289.
10 Gould, op. cit., p. 36.
11 Ibid.
12 Arcana Coelestia, no. 9555.
13 Swedenborg, Divine Love and Wisdom, no. 170.
14 Gould, p. 18ff.
15 Swedenborg, Economy of the Animal Kingdom, no. 248.
16 Ibid.
17 Ibid., no. 248.
18 Gould, op. cit., p. 59; Loren Eiseley, Darwin's Century (Garden
City, New York: Doubleday, 1958), p. 339.
19 Gould, op. cit., p. 36.
20 Herder, Ideen zur Philosophie der Geschichte (1784-1785), cited in
Gould, op. cit., p. 36.
21 Gould, op. cit., p. 36.
22 Lorenz Oken, Elements of Physiophilosophy (1847), p. 494, cited in
Gould, op. cit., p. 40.
23 Gould, op. cit., p. 45.
24 Swedenborg, Divine Love and Wisdom, no. 170.
25 Oken, op. cit., p. 19, cited in Gould, op. cit., p. 45.
26 Swedenborg, Conjugial Love, no. 361; Divine Love and Wisdom, no.
213.
27 Gould, op. cit., p. 37.
28 Ibid., p. 46.
29 Ibid.
30 Swedenborg, Arcana Coelestia, no. 3986:3.
31 Gould, op. cit., p. 47.
32 von Baer, Entwickelungsgeschichte der Thiere (Developmental History
of Animals), (1828), p.263, cited in Gould, op. cit., p. 54.
33 Ibid., p. 207, cited in Gould, op. cit., p. 56.
34 Ibid., cited in Nordenskjold, op. cit., p. 365.
35 Eiseley, op. cit., pp. 53-54.
36 See John R. Swanton, Emanuel Swedenborg: Prophet of the Higher
Evolution (New York: New Church Press, 1928).
37 Eiseley, op. cit., pp. 36-37.
38 Gould, op. cit., p. 76.
39 Ibid., pp. 6, 202-206.
40 Gould, op. cit., pp. 2-3.
41 Ernst Mayr, The Growth of Biological Thought (Cambridge, Mass:
Harvard Univ. Press, 1982), p. 475.
42 Nordenskjold, loc. cit.
43 Gould, op. cit., pp. 234-235.
44 See note 39.
45 Ibid., p. 206.
46 von Baer, op. cit., pp. 203-204, cited in Gould, op. cit., p. 54.
47 Unable to find reference.
48 Nordenskjold, op. cit., p. 333.
49 Swedenborg, Heaven and Hell, n. 460.
50 See note 45.
51 Gould, op. cit., p. 372.
52 L. Bolk, Das Problem der Menschwerdung (1926), cited in Gould, op.
cit., p. 357.
53 Gould, op. cit., pp. 400-404.
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