The Return of Teleology to Biology
- Brian Miller
In my last article I described the revolution occurring in systems biology where practitioners have replaced evolutionary presumptions with design-based assumptions. Now, I will detail how many systems biologists have given up the dogma that investigators should never appeal to teleology (aka design or purpose).
Biologists have faced a vexing dilemma since the philosophy of scientific materialism came to dominate Western thought. Life looks designed, but the gatekeepers of most mainstream scientific institutions have forbidden researchers from appealing to teleology as an explanation. Darwin’s theory of evolution appeared to offer an elegant solution to this quandary by positing natural selection as a designer substitute. Unfortunately, top theorists have publicly acknowledged that this mindless mechanism has no real creative power. But they have offered nothing to plausibly fill the explanatory deficit left in its absence (here, here).
Purging Teleological Language
Moreover, the most philosophically minded biologists have come to recognize that appealing to any evolutionary mechanism as a creative agent is logically incoherent. For instance, as David Hanke states in his essay, “Teleology: the explanation that bedevils biology”:
Biology is sick. Fundamentally unscientific modes of thought are increasingly accepted, and dominate the way the subject is explained to the next generation. The heart of the problem is that we persist in making (literal) sense of the world that we now know to be senseless by attributing subjective values to the objects in it, values that have no basis in reality.
He then lists several statements by none other than Richard Dawkins that embody this philosophical transgression:
Somatic cell divisions are used to make mortal tissues, organs and instruments whose ‘purpose’ is the promoting of germ line divisions.
The replicators that exist tend to be the ones that are good at manipulating the world to their own advantage.
Hanke acknowledges that life displays clear signatures of design, but he insists that reality must be the opposite of where the evidence naturally leads:
The bits of living things at all levels of scale from molecules to the whale’s tail also happen to have symmetry, precision, and complexity, clues that simply shout ‘purpose’ in the inquiring mind. This has to be wrong. Because they are not manufactured they cannot have been designed, and so no one ever had a purpose for them. They make themselves and so just exist, without purpose or intended use.
He dedicates the rest of his essay to arguing that attempts to identify the intent of a biological structure or trait lead biologists astray. Investigators should instead assume that their objects of study simply exist without any higher purpose to meet some biological goal.
Zoologist John Reiss presents similar denunciations in his book Not by Design: Retiring Darwin’s Watchmaker. He aims to convince biologists to purge all teleological language from their writing and thinking:
Life is not designed, or at least it shows no evidence of design for anything other than continued existence, which needs no designer. … To truly retire the watchmaker, … We must admit that there is not only not design but indeed not even ‘apparent design’ in the biological world, in the sense of entities doing any more than they need to do to continue to exist.
P. 356
He proposes that biologists instead appeal to paleontologist Georges Cuvier’s concept of the “conditions of existence” in a manner that appears to be the biological equivalent of the weak anthropic principle in cosmology.
Teleology as Guiding Principle
Hanke and Reiss’s feeble attempts to expel teleological language from biology in the face of the torrent of opposing data have proven as effective as attempting to use a toy sand bucket to hold back a striking tsunami. The most astute biologists now recognize that the only feasible approach to understanding biological systems is to understand their purpose.
This realization appears explicitly in the book System Modeling in Cellular Biology published by MIT Press:
…the main purpose of cellular control systems seems to be to guarantee reliable performance of vital functions under conditions of uncertainty (Lauffenburger, 2000; Csete and Doyle, 2002). Hence, elucidating high-level cellular design principles that could be exploited in systems modeling will require the simultaneous consideration of complexity and robustness in cellular networks…
A hope for understanding complexity in biology then is to uncover operational principles through a “calculus of purpose” (Lander, 2004) — by asking teleological questions such as why cellular networks are organized as observed, given their known or assumed function.
PP. 20, 24
Teleology as Biologists’ Mistress
In reality, researchers have long implicitly recognized that identifying a biological structure or system’s purpose was essential to understand it correctly. German physician and physiologist Ernst Wilhelm Ritter von Brücke (1819-1892) once observed:
Teleology is a lady without whom no biologist can live. Yet he is ashamed to show himself with her in public.
The difference now is that teleological language is becoming more explicit and central to investigations. A conflict will likely become increasingly evident between those who wish to remain true to their philosophical commitment to scientific materialism and those who desire to most effectively advance our understanding of the biological world.
