A Helpful Explanation of Evolution: Bruce Glass on “The Reconciliation of Christianity with Biological Evolution,” Part 1

I’ve just finished reading Bruce Glass, Exploring Faith and Reason: The Reconciliation of Christianity with Biological Evolution (Houston: DBG Publishing, 2012). The book was recommended by various scholars whom I respect, and for the most part I agree with their recommendation.

Glass is a religious agnostic and a non-scientist who writes to explain evolutionary theory to a popular audience and also to explain why it is not antithetical to classical orthodox and evangelical theology (he writes from a knowledge of pious evangelical Christians who are evolutionists). Glass’s writing is both lucid and permeated by an irenic spirit.

The book has eleven chapters divided into four Parts.

Part 1: Christianity and Evolution
1. God’s Word
2. God’s Creation
3. God’s Providence

Part 2: The Theory of Evolution
4. Layers of Understanding
5. The Awakening of Evolutionary Science
6. “Let the Land Produce Living Creatures”

Part 3: The Evidence of Evolution
7. Clues All Around
8. The History of Life
9. The Tree of Life

Part 4: The Politics of Evolution
10. “Creation Science” and Intelligent Design Theory
11. “Darwinism”

I found the book to be helpful in explaining biological evolution in a non-technical way. I’m going to comment on this in the current blog post (part 1) and also in the one following (part 2).

But I was less enamored with the strategy Glass used to reconcile Christianity and evolution. It showed a somewhat simplistic and bookish understanding of the Bible and theology. I’ll raise my criticisms in the final part of this post.

I found the real value of Glass’s book to be Part 2: “The Theory of Evolution” and especially Part 3: “The Evidence for Evolution.”

Part 2:“The Theory of Evolution” contains three lucid chapters. Glass is at his best explaining biological evolution in ordinary language so that non-scientists can make sense of it.

Chapter 4: “Layers of Understanding.” Here Glass clarifies what a scientific theory is (including the multiple ways the word “theory” is used) and how later scientific theories often explain matters that earlier theories can’t (without totally invalidating the earlier theory). This nicely diffuses the objection that evolution is “only” a theory (where theory means something like an unsupported hunch). It also illustrates one of the meanings of the word “layers” in the title of the chapter, namely, how earlier and later scientific theories relate to each other.

But “layers” has another meaning, namely, how science relates to faith. Glass helpfully also addresses the historical problem Christians have had when they related theology to science by the strategy of a “God of the gaps” (that’s when God is introduced to explain what science—at the moment—cannot explain). That science typically fills in the gaps, over time, thus squeezing God out of the picture should warn Christians about the folly of this approach (which is the basic problem with the “Intelligent Design” movement).

Chapter 5: “The Awakening of Evolutionary Science.” In this chapter Glass recounts Darwin’s intellectual development, his collection of specimens and observation of species diversity during the Beagle voyage, and how he came to develop his theory of “natural selection” to explain the mechanism of evolution. Glass notes that biological evolution did not begin with Darwin, and he summarizes how evolutionary theory has developed since Darwin, especially with the rise of genetics. This is a fine, clear exposition.

I would, however, have liked Glass to explain more fully the difference between Darwinian “natural selection” and Lamarckian “inheritance of acquired characteristics,” which are often confused in the popular mind, and which he declares incompatible (p. 92). Thankfully, he does this in a later chapter. It should be noted that Glass treats natural selection as the only viable account of evolution, even though there are supplementary mechanisms being proposed these days (including neo-Lamarckian proposals).

Chapter 6: “Let the Land Produce Living Creatures.” In this chapter Glass focuses on the multiple ways that life has proliferated on earth, including examples of “co-evolution” (in which species evolve in tandem, adapting to each other), the quite diverse paths through which complex structures (like eyes and wings) have developed in different organisms, and convergent evolution of different species filling similar niches in different parts of the world (such as evident similarities between marsupial mammals and placental mammals, which developed separately).

Glass also helpfully explains how biological evolution with greater complexity can occur in a universe defined by entropy (which initially seems counter-intuitive). And he makes the important admission that Darwin’s evolutionary theory can explain how life evolves, but does not actually explain biogenesis or the origin of life (p. 120). Although there is much current speculation on how life began, there is no accepted scientific explanation.

In my next post I’ll discuss Glass’s superb explanation of the evidence for evolution, especially the chapter that is proverbially worth the price of the book.