Vitalism - Biology

Biology

With the rise of mechanism in science in the 16th century there were few vitalistic scientists left. These included the English anatomist Francis Glisson (1597–1677) and the Italian doctor Marcello Malpighi (1628–1694).

Caspar Friedrich Wolff (1733–1794) is considered to be the father of epigenetic descriptive embryology, that is, he marks the point when embryonic development began to be described in terms of the proliferation of cells rather than the incarnation of a preformed soul. In his Theoria Generationis (1759), he endeavored to explain the emergence of the organism by the actions of a "vis essentialis", an organizing, formative force, and declared "All believers in epigenesis are Vitalists."

Johann Friedrich Blumenbach established epigenesis as the model of thought in the life sciences in 1781 with his publication of Über den Bildungstrieb und das Zeugungsgeschäfte. Blumenbach cut up freshwater polyps and established that the removed parts would regenerate. He inferred the presence of a "formative drive" (Bildungstrieb) in living matter. But he pointed out that this name, "like names applied to every other kind of vital power, of itself, explains nothing: it serves merely to designate a peculiar power formed by the combination of the mechanical principle with that which is susceptible of modification". Therefore early vitalists were aware that the vital forces that they proposed were not capable of standing as positive scientific theories.

Vitalism was revived in the early 18th century by the physician Marie François Xavier Bichat, and the physician John Hunter who recognized a "living principle" in addition to mechanics.

Between 1833 and 1844, Johannes Peter Müller wrote a book on physiology called Handbuch der Physiologie, which became the leading textbook in the field for much of the nineteenth century. The book showed Müller's commitments to vitalism; he questioned why organic matter differs from inorganic, then proceeded to chemical analyses of the blood and lymph. He describes in detail the circulatory, lymphatic, respiratory, digestive, endocrine, nervous, and sensory systems in a wide variety of animals but explains that the presence of a soul makes each organism an indivisible whole. He also claimed the behavior of light and sound waves showed that living organisms possessed a life-energy for which physical laws could never fully account.

Vitalism was also important in the thinking of later teleologists such as Hans Driesch (1867–1941). In 1894, after publishing papers on his experiments on sea urchin eggs, Driesch wrote a theoretical essay entitled Analytische Theorie der organischen Entwicklung, in which he declared that his studies in developmental biology pointed to a "blueprint" or teleology, an Aristotelian entelechy, a scientific demonstration of Immanuel Kant's notion that the organism develops as if it has a purposeful intelligence:

Development starts with a few ordered manifoldnesses; but the manifoldnesses create, by interactions, new manifoldnesses, and these are able, by acting back on the original ones, to provoke new differences, and so on. With each new response, a new cause is immediately provided, and a new specific reactivity for further specific responses. We derive a complex structure from a simple one given in the egg.

His main argument was that when one cuts up a sea urchin embryo after its first division or two, the parts do not become parts of sea urchins, but complete sea urchins. However, later research on cell fate determination has led to successful explanations that do not involve vitalism. The embryo's cells remain totipotent stem cells for the first few cell divisions, only becoming specialized later. Driesch's reputation as an experimental biologist deteriorated as a result of his vitalistic theories. He moved to Heidelberg and became a Professor of Natural Philosophy.

The vitalists strongly rejected Darwin's theory of natural selection. Because of their teleological leanings, they strongly rejected his selectionism. As Darwin's theory of evolution denied the existence of any cosmic teleology, the vitalists saw Darwin's theories as too materialistic to explain the complexity of life. Driesch was a strong anti-Darwinian.

Other vitalists included Johannes Reinke and Oscar Hertwig. Reinke used the word neovitalism to describe his work, he claimed that it would be eventually verified through experimentation and wanted an improvement over the other vitalistic theories. The work of Reinke was an influence for Carl Jung.

Alfred Russel Wallace believed qualitative novelties could arise through the process of evolution, in particular the phenomena of life and mind; like the vitalists Wallace attributed these novelties to a supernatural agency. Later in his life, Wallace was an advocate of spiritualism and believed in a non-material origin for the higher mental faculties of humans. He believed that evolution suggested that the universe had a purpose, and that certain aspects of living organisms were not explainable in terms of purely materialistic processes as written in a 1909 magazine article entitled The World of Life, which he later expanded into a book of the same name.

A number of physicists began to advocate vitalism. Niels Bohr was one of the first to suggest that special laws not found in inanimate matter might operate in organisms. He thought of these laws as analogous to the laws of physics except for their being restricted to organisms. Erwin Schrödinger supported similar ideas, as well as the physicists Walter M. Elsasser and Eugene Wigner.

John Scott Haldane adopted an anti-mechanist approach to biology and an idealist philosophy early on in his career. Haldane saw his work as a vindication of his belief that teleology was an essential concept in biology. His views became widely known with his first book Mechanism, life and personality in 1913. Haldane borrowed arguments from the vitalists to use against mechanism; however, he was not a vitalist and he insisted that Hans Driesch's view of entelechy was unacceptable as it was inconsistent with the law of conservation of energy. Haldane treated the organism as fundamental to biology: "we perceive the organism as a self-regulating entity", "every effort to analyze it into components that can be reduced to a mechanical explanation violates this central experience". The work of Haldane was an influence on organicism.

By the 1930s vitalism had fallen out of favour by most biologists. In 1931 John Scott Haldane stated:

Biologists have almost unanimously abandoned vitalism as an acknowledged belief. —

Haldane also stated that a purely mechanist interpretation can not account for the characteristics of life. Haldane wrote a number of books in which he attempted to show the invalidity of both vitalism and mechanist approaches to science. Haldane explained:

We must find a different theoretical basis of biology, based on the observation that all the phenomena concerned tend towards being so coordinated that they express what is normal for an adult organism. —

The demise of vitalism instead of leading to a victory of mechanism lead to a number of new approaches to science. These new approaches to science included holism, organicism, and emergent evolution.

On discussing the history of vitalism in biology Ernst Mayr wrote in 1988:

Vitalism has become so disreputable a belief in the last fifty years that no biologist alive today would want to be classified as a vitalist. Still, the remnants of vitalist thinking can be found in the work of Alistair Hardy, Sewall Wright, and Charles Birch, who seem to believe in some sort of nonmaterial principle in organisms.

Some non-scientists have recently defended forms of vitalism, such as arguments for the existence of an immaterial "life force" or that a purposive influence or force is guiding the course of biological evolution.