Darwin's Doctrine of Evolution Vs. Aristotle's Teleological Explanation
The need to understand organisms has been a much sought goal of science since its
birth as biology. History shows Aristotle and Charles Darwin as two of the most
powerful biologists of all time. Aristotle's teleological method was supported widely
for over 2,000 years. One scientist remarks that the Aristotelian teleology "has been
the ghost, the unexplained mystery which has haunted biology through its whole history"
(Ayala, 10). If Aristotle's approach has frightened biology, then Darwin, who actually
nicknamed himself the "Devils Chaplain," and his idea of natural selection has virtually
dissected Aristotle's ghost. While Aristotle explained biology through a plan and a
purpose, Darwin debated that randomness and chaos are responsible for the organic world
as we know it. Guiseppe Montalenti, an Italian geneticist and philosopher of biology,
wrote that Darwin's ideas were a rebellion against thought in the
Aristotelian-scholastic way (Ayala, 4). In order to understand how Darwinism can be
considered a revolt against Aristotle, we must first inspect Aristotle's ideas and
thoughts about biology.
Aristotle used teleology to explain the harmony and final results of the earth.
Teleology is the study of the purpose of nature. Aristotle believed that scientists
should follow the plan adopted by mathematicians in their demonstrations of astronomy,
and after weighing the phenomena presented by animals, and their several parts, follow
consequently to understand the causes and the end results. Using this method, Aristotle
constructed causes for body parts and processes of the human body, such as sundry types
of teeth. Aristotle elucidated on this topic: "When we have ascertained the thing's
existence we inquire as to its nature...when we know the fact we ask the reason" (Evans,
82).
Despite Aristotle's frequent teleological explanations, he did warn against teleology
leading to misinterpretations of facts. In a short writing on the reproduction of bees
in Generation of Animals, Aristotle was troubled that there were insufficient
observations on the subject, and warns that his theory is dependent on facts supporting
the theory. One twentieth century biologist believes that Aristotle did not often
enough follow his own advice. Ayala printed that Aristotle's "error was not that he used
teleological explanations in biology, but that he extended the concept of teleology to
the non-living world."(56)
Some biologists say Aristotle used teleology so often because order and purpose, both in
the universe and life, were immensely important to him. Aristotle thought it was both
ridiculous and impossible that chance, which is not linked with order, could be used to
explain occurrences in biology. In one of his writings, he criticized Empedocles for
the use of chance to describe biology. Aristotle believed that Empedocles, then, was
in error when he said that many of the characters presented by animals were only the
results of incidental occurrences during their evolutionary growth.
As a vitalist, Aristotle's philosophy also had a powerful influence on what he
wrote. His beliefs are described in On the Soul and On the Generation of Animals.
These thoughts can be epitomized into four main areas of Aristotle's vitalistic belief:
1. He connects the life of an organism with its psyche.
2. He finds purposefulness and organic unity as the most significant sections of
vitalism.
3. He debates that the entire body, rather than the parts, should be taken into
account.
4. He emphasizes the soul as the final goal.
Looking at these four traditions, it is not shocking that Aristotle thought that single
limbs, such as an arm, was a good description of organisms. This could be compared to a
house being called bricks and mortar. Rather than concentrate on individual variability
and individual pieces, Aristotle believed that it was proper to concentrate on the "final
cause" of the entire entity. Aristotle accepted that the "soul" was probably the final
cause, and his Parts of Animals says "now it may be that the form of any living creature
is soul, or some part of soul, or something that involves soul.
Aristotle's ideas and traditions continued on their path long after his physical shell
passed away. In the 12th and 13th century, Aristotle's philosophy was re-founded and
incorporated into Christian philosophy by St. Thomas Aquinas. During the Renaissance,
when the earth was discovered to no longer be the center of the universe, Aristotle's
astronomical systems broke down, but his biological theories remained intact. This does
not mean all people accepted Aristotle's theories during the Renaissance, however. One
philosopher from the twentieth century, Mayr, accuses Aristotle's teleology of the
non-organic world for the refutation of Aristotle by Descartes and Bacon. Both of these
men criticized "the existence of a form-giving, finalistic principle in the universe" and
believed this rejection demanded the removal of all teleological uses-even biology (Mayr,
38).
Scientists were forced to look over the concept of living things again when time was
discovered in the 18th century. With the exception of Heraclitus and Lucretius, most
scientists had described a static world. Once Buffon remade the geological structure of
the earth, and put it into a series of stages, all scientists were forced to account for
this new information that the world was much older than originally thought. This formed
the field of Paleontology. The information gained from paleontology and the "new"
geology was necessary to the evolutionary argument. Deists, however, created another
explanation for the creation of the world; God created the world and then gave it a set
of laws that guided the world into perfection (Mayr, 57).
The use of natural theology helped stabilize religion. By the mid 1850's, the sciences
of psychics and chemistry were used to explain the unknown forces, such as gravity, that
were previously associated with religion. The general population still felt safe with
their beliefs because they agreed to the above deist explanation of the history of the
earth and because biological functions were continually explained in conjunction with a
creator. Theology in the English Protestant Church was documented through "Natural
Theology," the "demonstration of the goodness of god by the contemplation of nature and
the benevolent artifice which seemed everywhere to demonstrate" (Burrow, 17). The church
at this time, of the Victorian Era, was very dominating. The Christian heritage was
flourishing in this epoch of regulation and purpose.
The only dissension from the austere Victorian Era was from a man named Lamarck. In 1809
he published Philosophie Zoolique, in which he intended to prove that organic structures
gave rise to additional organs when needed and that these new organs were passed onto
their progeny (Ayala, 9). Lamarck's hypothesis of evolution embodied the two main
standards to include: 1) there is an inherent drive towards progress; and 2) that there
is a birthright of traits that are acquired characteristics (Simpson, 266).
For some reason, the study of natural history became immensely popular in the early
nineteenth century. Exploring nature was seen as a way to explore God and natural
theology. Because such exploration was easy to accomplish, unlike astronomy (which
required mathematics) things like trees and birds were studied by common folk as well as
scientists. This popularity was proven when the initial 1,250 copies of Darwin's Origin
of the Species sold out in one day (Burrow, 19).
Charles Darwin was one of history's most knowledgeable biologists and ranks with some of
the greatest intellectual heroes of mankind (Simpson, 268). After several career changes,
Darwin became a naturalist. In 1831, he began a position as a naturalist on the H.M.S.
Beagle, an exploration vessel that needed a naturalist to keep a record of the ship's
biological discoveries (Moore, 9). When Darwin began this trip, he shared the popular
belief that every organism was created to suit its environment and that there was order
and harmony in nature. When Darwin returned to England five years later, he still
believed there was harmony in nature but now doubted in perfect adaptation. Instead, he
believed in transmutation of the species (each species is a descendent of an earlier
species and that the traits are inherited) (Moore, 10).
Darwin's metamorphosis occurred during a time when many naturalists were beginning to
reject the teleological approach to explaining biological shapes. One biologist, Sir
Thomas Henry Huxley, felt the renewed inspection of evolution was going to be the
extinction of teleology. Huxley said, "The doctrine of evolution is the most formidable
opponent of all the common and courser forms of Teleology...The Teleology which supposes
that the eye, such as we see it in man or one of the higher vertebrate, was made with the
precise structure it exhibits, for the purpose of enabling the animals which possesses
it to see, has undoubtedly received its death blow" (Ayala, 228).
Darwin realized that with the teleological approach contrary to his views, he should
attempt to shed doubt on the ideas of a fixed relationship between an organism and its
environment. One example of Darwin's powerful debates against teleology includes winged
yet flight-less beetles. In trying to prove that some organisms have extremities that
are useless to them, Darwin says "if simple creation, surely it would have [been] born
without them [the wings]" (Ospovat, 26).
Even though Darwin rejected the idea of teleology, he still very much respected its
"creator," Aristotle. Darwin appreciates Aristotle's contribution to biology so much
that he is mentioned in the opening paragraph of Origin of the Species. Darwin also
praises his pioneering work, and recognizes his role in knowledge now common, but to have
discovered and theorized such principles in Aristotle's time, Darwin considers an
amazing discovery. In 1860 Darwin wrote Asa Gray, "I cannot think the world as we see it
is the result of chance; and yet I cannot look at each separated thing as the result of
Design...I am, and shall ever remain, in a hopeless muddle." According to Ayala, this
thought shows that while Darwin has a mechanistic viewpoint, he is never truly denying
any sort of evolutionary viewpoint to its fullest; he is simply stating that which he
believes in (225).
However much confused about teleology, Darwin did not think the world should be
explained in terms of its purpose in the universe. Once, Darwin asked the question,
"What would the astronomer say to the doctrine that the planets moved not according to
the laws of gravitation, but from the creator having willed each separate planet to move
in its particular orbit?" (Burrow, 48). Darwin is referring to the breakdown between
astronomy and religion, physics and chemistry that happened during the Renaissance
period. Darwin suggested the inclusion of biology as a hard science so that other
sciences like physics and chemistry would not be unfairly built on the organization of
knowledge, based on testable, working hypotheses.
The theory of evolution was not formed by Darwin. Ideas of man progressing from smaller
life existed even in Ancient Greece. Empedocles' evolution theory involved "the coming
together of limbs," while Xenophanes thought that humans came into existence "from earth
and water." Darwin's beginning to the Origin of the Species is mostly a listing of
antecedents to philosophers of evolution, and what views they held. One of these
predecessors was Darwin's grandfather, Eramus Darwin.
Why Charles Darwin was more "powerful" than the other evolutionary scientists was his
theory of natural selection as the vehicle of evolution. Darwin credits the inspiration
of his natural selection theory to reading T.R. Malthus' Essay on Population (1798). In
this essay, Malthus tried to show an equilibrium viewpoint-unless checked by famine,
disease or voluntary restraint, population growth will outrun food supply. Darwin's
theory was finished by the time he wrote the "sketch of 1842" but he did not release it
for twenty years because he wanted to produce a large work with both his own evidence for
his ideas, and evidence of other naturalists (Ospovat, 1). Darwin was made to publish
his own theory earlier than planned, when he learned that another naturalist was
planning to publish a similar one. (Coincidentally, the other naturalist, Alfred
Wallace, was inspired by the same essay).
Darwin's theory completely changed biological philosophy. With his theory came the
recognition that the self(individual) is the most vital unit of biological change, and
that this polymorph happens due to total chance. In his theory, Charles Darwin suggested
that there is a "Struggle for existence." This "struggle" was later put into use for
support within several arguments. British Imperialists attempted to rationalize their
operations by arguing that Darwinism suggested the strong must overpower the weak. In
the late 19th century, "Passionate Nationalism" caused members of each nationality to
trust that their nation was the most powerful. And, in the early 20th century, Hitler
and other Nazi party members used Darwin's work to suggest the "biological necessity" for
war and survival of the fittest...In this case, Hitler was referring to the Aryans.
Such controversies could not be upheld using biological ideas of Aristotle, since his
conception of species included the abstraction that all individuals were alike. Distinct
differences, like eye color, are inconsequential because they are not promoted by a
conclusive objective. However, individual contrarieties are the cornerstone of evolution
through natural selection. Without these differences, evolution could not come to pass.
For this reason, individuality is seen by biologists as the most meaningful trait of
biological organisms. A few scientists try to describe evolution teleologically. This
proof, of course, is not possible, as evolution through natural selection cannot be
described as goal-oriented since it happens due to previous events or transformations,
not in anticipation of coming events. If we were goal-oriented, natural selection would
not be supple enough to be useful in rapidly changing environments (Mayr, 43).
REFERENCES CONSULTED
Aristotle. The Works of Aristotle, Encyclopedia Britannica. New York, 1952
Ayala, F.J. and Tobzharsky, T. Studies in the Philosophy of Biology. University of
California Press. Berkeley and Los Angeles. 1974.
Burrow, John. Editor introduction to Charles Darwin's Origin of the Species Penguin
books. England, 1968.
Evans, G. The Physical Philosophy of Aristotle. University of New Mexico Press.
Albuquerque, 1964.
Kirk, G., Raven, J. and Schofield, M. The Presocratic Philosophers. Cambridge
University Press. Cambridge. 1983.
Mayr, Ernst. Toward a New Philosophy of Biology. Harvard University Press. 1988.
Moore, Ruth. Evolution. Time-life books. Alexandria, Virginia. 1980.
Simpson, George The Meaning of Evolution. Yale University Press. New Haven and London.
1949.
The Effects of Aristotelian Teleological Thought on
Darwin's Mechanistic Views of Evolution
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