Monday, June 21, 2010

From the first day of class

Today was the opening lecture of introductory biology. The point of this lecture was defining biology--which means defining life, and defining science. Unfortunately, it is impossible to define either of those terms satisfactorily. However, there are some things that most of those who study life seriously can agree upon. One of these is that "vitalism," or "Elan vitale" is a hypothesis that has been repeatedly shown to be false. Another of these is the role of falsifiability in constructing and testing hypotheses.

I was reminded by both of these by a collection of commentary that V. sent me in response to the news of Synthia, Craig Venter's synthetic life form. One of the contributors to this feature in the journal Nature wrote the following:

Arthur Caplan
Professor of bioethics, University of Pennsylvania

Venter and his colleagues have shown that the material world can be manipulated to produce what we recognize as life. In doing so they bring to an end a debate about the nature of life that has lasted thousands of years. Their achievement undermines a fundamental belief about the nature of life that is likely to prove as momentous to our view of ourselves and our place in the Universe as the discoveries of Galileo, Copernicus, Darwin and Einstein.

More than 100 years ago, the French philosopher Henri-Louis Bergson claimed that life could never be explained simply mechanistically. Nor could it be artificially created by synthesizing molecules. There was, he argued, an “élan vital” — a vital force that was the ineffable current distinguishing the living from the inorganic. No manipulations of the inorganic would permit the creation of any living thing.

This ‘vitalist’ view has come in many forms over the centuries. Galen wrote of the ‘vital spirit’ in the second century; Louis Pasteur in 1862 looked to ‘vital action’ to explain how life exists; and the biologist Hans Driesch posited an ‘entelechy’ or essential force as a requisite for life as recently as 1894. The molecular-biology revolution notwithstanding, science has continued to struggle with the reducibility of life to the material. Meanwhile, Christianity, Islam and Judaism, among other religions, have maintained that a soul constitutes the explanatory essence of at least human life.

All of these deeply entrenched metaphysical views are cast into doubt by the demonstration that life can be created from non-living parts, albeit those harvested from a cell [italics mine]. Venter’s achievement would seem to extinguish the argument that life requires a special force or power to exist. In my view, this makes it one of the most important scientific achievements in the history of mankind.
I think he completely misses; I think he shoulda sat in on my class today. First, vitalism has been decidedly the opposite of vital for over a century; Wohler's synthesis of urea in 1828 was the first nail in the coffin, and synthesis-from-scratch of biomolecules and even intact, biologically active viruses have been bolting down the lid and sealing the sarcophagus ever since. Perhaps this can be let slide, as the author's expertise is mainly in the ethics of organ transplantation.

The other thing is that Venter's work does not refute vitalism; it does not adequately test or falsify the hypothesis that there's something special about "living" chemicals. A critical step, essential to the success of the experiment, was for the artifical, synthetic DNA to be passed through and replicated in a living cell. This DNA, which I could argue had picked up some of that je ne sais quoi of elan vitale, was then used to reboot a previously living cell that had its DNA removed; said cell could also be argued to be full to the gills of vital essence. Far from falsifying vitalism, it could be argued that this experiment actually strengthens the case. (George Church correctly argues in the same publication that the creation of Synthia does "not really...test vitalism.")

I'm not sure what my point is; ever since it ran a cover article about homeopathy in 1988, we have known to take the journal Nature with a grain of salt. Personal experience suggests the risks of trusting anybody just because they have a Ph.D. Personal experience also suggests that between 5 and 20 percent of students will sleep through or text or play video games through any given college lecture. I just hope that my students do better than this guy.

No comments:

Post a Comment