Monday 25 May 2015

Donald Campbell: Pioneer of Universal Darwinism

It's well known that Donald Campbell was an early pioneer of cultural evolution. Most in the field acknowledge his work as influential or historically important. One of his early papers on "Blind variation and selective retention" dates from 1960. Later in life, Donald Campbell explored the limits of evolutionary theory - applying it to a range of inorganic phenomena. In particular, there's the following paper:

Bickhard, Mark H. and Campbell, Donald T. (2003) Variations in Variation and Selection: The Ubiquity of the Variation-and-Selective-Retention Ratchet in Emergent Organizational Complexity. Foundations of Science, 8(3), 215–282.
Here, Campbell and Bickhard apply the principles of variation and selection to a range of phenomena - including why gravel accumulates at the edges of roads, crystal growth, crystal stability, the formation of atoms and molecules and catalysis. They argue that "energy wells" are common causes of selection phenomena - giving rocks, planets, stars, and galaxies as examples.

Campbell mostly avoids the terminological debate about whether such phenomena qualify as being "Darwinian" - which is still the source of much modern noise and confusion. Instead he uses terminology oriented around the terms "variation" and "selection" and examines whether they produce "goodness of fit", "adaptation" and "evolutionary historicity".

There seem to be some differences between my understanding of this area and Campbell's (which admittedly dates from the 1990s). I would give examples of tree-like phenomena in nature - such as electrical discharges, propagating cracks, fractal drainage patterns and diffusion-limited aggregation - and say they these trees are family trees, showing clear ancestor-descendant relationships. I make that argument in more detail on my positional inheritance page.

Another apparent oddity of Campbell's perspective is that none of his examples of selection seem to involve things being destroyed. Death is a common source of selection in the organic realm - so it seems natural to me to give instances of destruction as examples of selection in the inorganic realm. For example, the destruction of islands by the sea, of rocks by landslides, of sediments by subduction, and of pebbles by erosion all seem to me to be fine examples of selection. Campbell seems to me to systematically steer clear of destructive examples. However, this seems like a very curious thing to do. Did Campbell really not regard destruction as being a source of selection?

Though Campbell still seems to me to have a bit of a restricted perspective on the scope of selective explanations, he applied the concepts of selection, fitness and adaptation deeply into the realms of physics and chemistry in the 1990s. That makes him into one of the pioneers of Universal Darwinism.

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