Wednesday, April 29, 2009

On Theistic Evolution

Concerns have been raised about an article on this blog which appears to promote theistic evolution, i.e., an evolutionary process which took place under God’s guidance. We want our readers to know that the contributors to this blog are by no means in agreement on the scientific and theological validity of theistic evolution, and we further assure them that its promotion is not a “hidden agenda” of this blog.

Theistic evolution is accepted, however, among an increasing number of Bible-believing, orthodox Christians. For that reason we believe that we must discuss the theological and scientific issues surrounding the theory among ourselves and also on the blog. It is an issue that we may not be able to resolve adequately but that we also do not, for that reason, want to censor or “run away from.” Informed readers will be able to appreciate the difficulties faced by biologists who encounter what appears to be scientific evidence for evolution but wish to remain faithful to Scripture and the Reformed confession. We do not want to ignore this difficulty and we hope that on our blog the matter can be discussed publicly, in a brotherly way, without acrimony.


Fritz said...

One VERY CURIOUS observation which might suggest that all life on Earth has a common origin was described by Richard Feynman in a lecture he gave on symmetry in physics. It's especially interesting to me because maybe it illuminates a key issue: The experiment and its result is simple enough for anyone to understand. But what does it mean? How does one explain it? Who gets to wield Ockhams razor?
---< Richard Feynman >---
Say we make a solution of common sugar in water. We then shine a polarized light source through that sugar solution and observe the light on the other side. We will notice that the plane of polarization of the light has been rotated from the original, and that it has rotated to the right.

Now let’s hypothetically construct some sugar artificially. It’s not hard to do, but we won’t go into the process here. We’ll dissolve that sugar in water, and shine the same polarized light into it. Oddly enough, we discover that the light’s polarization hasn’t rotated at all!

Now, let’s add some bacteria to the water and let them eat some of the sugar. After a few minutes, we’ll then shine the light through the container again. Wait a minute! The light exiting the container has rotated now, all right — but to the LEFT!

What happened? The natural sugar rotated the plane of polarization to the right because natural sugar — glucose, in particular a form of glucose called dextrose or d-glucose, has a right-handed helical structure. When we created our synthetic sugar, we made something with the right chemical formula, but it actually contained equal parts of d-glucose (dextrose) and l-glucose, which is left-handed! The rotations cancelled and we saw no effect until we added bacteria.

All life that we’re aware of, right down to bacteria, either produces or uses right-handed sugar molecules. The bacteria ate only the d-glucose, having no use for the l-glucose since it can’t break it down for use as food because the enzymes don’t fit! We were then left with an l-glucose solution that rotated the plane of polarization to the left.

---< End >---

Fritz Dewit

Arnold Sikkema said...

Fritz: This chiral asymmetry of life is certainly very interesting. It is even used in a recent study [S. Pizzarello et al., PNAS 105:10 (11 March 2008) 3700-04 – click here for the abstract] of the chemical composition of meteorites to lend support to the idea that life on earth originated in an extraterrestrial “seeding”. If you watched Expelled (which one colleague calls a “docuganda”, and which I review in seven words as “provocative, effective, funny, but biased, simplistic, overblown”), you will have seen the popular atheist Richard Dawkins lending support to the possibility of intelligent design by extra-terrestrials seeding our planet with life. Seeding aside, I think most would agree that a strikingly similar characteristic (like chiral asymmetry, genomics, body plans) can be marshaled as evidence of a common origin. But there would be disagreement on the nature of this common origin: is it common ancestry apart from divinity, is it God the Creator apart from any common ancestry, or is it God providentially acting through common ancestry?