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Scott Turner Explains Philosophical Traditions Shaping Biology

Photo: Statue of Philosophy, Reading Room, Library of Congress, by Carol M. Highsmith, via Flickr.

In my previous article, I introduced Scott Turner’s new video course on his heterodox evolutionary model. Today, I will describe his two-part lesson on the philosophical traditions that have shaped different biological viewpoints (part 1part 2). His insightful analysis helps to bring much greater understanding to the true conflict between the standard evolutionary model and intelligent design. It also lays the philosophical framework for his own model. 

The Rise of Philosophy

Turner begins by outlining the development of the different philosophical schools that would shape the course of Western civilization. He begins by describing how nearly every ancient culture developed some mythology describing the origin and primal history of the world. A common feature was the centrality of a supernatural agent or agents, such as a pantheon of deities, driving history forward. In the 6th century BC, the Greeks introduced an entirely new approach to understanding the world that was based on philosophy. The discipline of philosophy studies, among other subjects, the nature of nature. Its practitioners attempt to understand the world not based on myths but on reason. 

The ancient philosophers examined the foundational questions about reality. One question of foremost importance was how to understand the tension between the world having many fixed properties (i.e., the world as being), such as the density of water, and also in many ways always changing (i.e., the world as becoming). Another central question was whether life was unique or simply another arrangement of common materials. Related questions concerned the differences between the various forms of life and how those differences came to be. 

The Atomist School

One prominent school of philosophy was the atomists. They attempted to answer these questions by proposing that everything was made of eternal “atoms” that interacted according to various rules. The fixed properties of entities then resulted from the unchanging nature of the atoms and their associated rules. The differences between different entities and their tendency to change resulted from the atoms constantly associating into different configurations. A key goal of the atomists was to remove the need for agency from the world, so humanity could be liberated from the gods. People could then be set free. The proponents of this school would be the ancient version of militant atheists. 

The most famous atomist was Democritus who lived in the 5th century BC as a contemporary of Socrates. He had a disciple named Anaxagoras who applied the atomist framework to life. He postulated that the diversity of life arose from a large ensemble of body parts floating in a neverland. The parts randomly interconnected like with a Mr. Potato Head toy. Some associations of parts represented nonviable monstrosities, such as those with arms where their mouths should be, while others corresponded to functional organisms. The former did not persist, while the latter survived and reproduced. This narrative has a certain resonance with Darwinian natural selection, but it was designed to explain the origin of organisms without the appeal to agency, not to explain how organisms evolve over time.  

Socrates and Teleology

The atomists’ contemporary critics believed that attempting to abolish agency from the world was impossible. Socrates described the idea as “next door to madness.” He instead insisted that the universe demonstrated clear and pervasive evidence of purpose in how virtually everything appeared directed toward a purposeful end. This belief is termed teleology, which means the doctrine of purposefulness. 

The atomists did not believe that any purpose existed in nature. Everything could be explained in terms of cause and effect — the rules governing the interaction of atoms. In contrast, Socrates and his disciples did not believe cause and effect were sufficient to understand the universe. The universe appears to be directed toward an end. Causation might be the means by which the universe drives toward that end, but causation is not the end itself. To understand the universe, one had to understand the purpose toward which it was directed. 

Plato and Aristotle

Socrates’ best known disciple was Plato, and he called that ultimate purpose the final cause or prime mover. The personification of the prime mover he termed the demiurge. All of the individual causes in the world were directed through the demiurge to conform to the final cause. The theologian Augustine associated a Christianized version of the demiurge with God. 

A central facet of the universe’s purpose was the existence of ideals. They were perfect representations of everyday objects that existed in an ultimate mind. This belief divorces Plato’s understanding of biology from that of the atomists. According to Plato, living organisms were not the result of chance arrangements of parts that happened to survive. They were manifestations of transcendent ideals or “forms” that acted as the blueprints the demiurge used to craft them. The deep resonance with intelligent design should be self-evident. 

The foremost disciple of Plato was Aristotle, and he followed in Plato’s footsteps in his opposition to the atomists’ denial of the centrality of purpose (aka teleology) in understanding the world (herehere). Yet, he differed from Plato in not locating the forms in an ethereal realm. Instead, he asserted that a form was inextricably bound up with a body. In the case of life, the form of an animal directed an embryo toward the goal of the adult architecture. Aristotle, like Plato, believed that form transcended and governed the matter that composed an object, and it originated in the mind of a supreme intellect (herehere).

Aristotle’s views of life provide the philosophical foundation for Scott Turner’s evolutionary model. The idea of form corresponds to Turner’s foundational premise of cognition directing the adaptation of an organism to its environment or the immediate environment to the organism’s physiological needs. Cognition also drives adaptive evolution. 

The Legacy of the Greek Philosophers

Turner concludes his lesson by charting the history of how these three schools shaped philosophers’ and scientists’ understanding of biology through the middle ages, into the Scientific Revolution, and up to today. The three schools were all influential in antiquity. During the medieval period, atomism waned. And Christians integrated Platonic and Aristotelean philosophy into what was termed natural theology. During the early modern period, the Platonic and Aristotelian views of nature diverged, disrupting natural theology. And atomism reemerged and became increasingly dominant with the rise of physics and chemistry. The modern form of atomism is termed scientific materialism.  

Of particular importance, Turner describes the subsequent fragmentation of biology into three divergent paths. The path that followed the atomist/scientific materialist outlook led to the rise of molecular biology and eventually neo-Darwinism. The path that followed the Aristotelean outlook focused on internal process and mechanism. It gave rise to physiology and ontogeny (aka developmental biology). On the Platonic branch, researchers focused on living form (e.g., body plans), which led to modern taxonomy and systematics. Turner classifies the intelligent design movement as a resurgence of Platonic idealism. 

Turner’s philosophical overview is an invaluable resource for anyone who wishes to understand the underlying assumptions that shape evolutionary theory and the different biological subdisciplines. It also provides an essential starting point for those in the mainstream evolutionary community to meaningfully dialogue with those holding the intelligent design perspective. And it lays the philosophical foundation for fully appreciating Turner’s innovative approach to evolutionary adaptation. 

Scott Turner welcomes any feedback to his course. His contact information and publications can be found at his website