Saturday 30 November 2013

Stephen Pinker on memetics in his latest book

Longstanding meme critic, Stephen Pinker has some more critical comments on memes in his latest book. Over to Stephen:

I think that that mind-life parallel inherent in memetics holds out the promise of new ways of understanding cultural and historical change, but that it also poses a danger.

Many theorists, partly on the basis of Dawkins's arguments about the indispensibility of natural selection in explaining complex design in living things, write as if natural selection, applied to memes rather than genes, is the only adequate explanation of complex design in human cultural achievements. To bring culture into biology, they reason, one must show how it evolved by its own version of natural selection. But that doesn't follow, because the products of evolution don't have to look like the process of evolution. In the case of cultural evolution they certainly don't look alike - human cultural products are not the result of an accumulation of copying errors, but are crafted through bouts of concerted brainwork by intelligent designers. And there is nothing in Dawkins's Universal Darwinism that makes this observation suspect. While it remains true that the origin of complex design on earth requires invoking selection (given the absence of any alternative mechanisms adequate to the task), in the case of complex design in culture, we do have an alternative, namely the creative powers of the human brain. Ultimately we have to explain the complexity of the brain itself in terms of genetic selection, but then the ladder can be kicked away, and the actual process of cultural creation and transmission can be studies without prejudice.

This is mostly the same bunch of confused notions that I criticized in my "Pinker takedown" series of videos from 2011.

This time, Pinker doesn't name the "many theorists" whose ideas he is criticizing. I doubt that they exist - because the idea involved just isn't what Pinker says. The basic idea of selectionism - since Donald Campbell proposed the idea in the 1960s - has been that adaptation and goodness-of-fit is the product of variation-and-selection mechanisms - or their products - and that the products of variation-and-selection mechanisms often themselves contain variation-and-selection mechanisms within them. Here's the relevant section from Campbell (1974):

  1. A blind-variation-and-selective-retention process is fundamental to all inductive achievements, to all genuine increases in knowledge, to all increases in fit of system to environment.
  2. The many processes which shortcut a more fully blind-variation-and-selective-retention process are in themselves inductive achievements, containing wisdom about the environment achieved originally by blind variation and selective retention.
  3. In addition, such shortcut processes contain in their own operation a blind-variation-and-selective-retention process at some level, substituting for overt locomotor exploration or the life-and-death winnowing of organic evolution.
Pinker criticizes the first point, agrees with the second point, but seems to be completely missing the third point. The human mind is simply not an alternative to variation-and-selection mechanisms. It works via variation-and-selection mechanisms. There's selection between ideas within individual minds. There's selection between synapses competing for attachment points. Selection acts between axon/dendrite growth tips competing for nutrients - and so on. The brain is a Darwin machine. This idea has long been recognized by neuroscientists. For more details about this, see my article titled: Keeping Darwin in mind.

Cultural evolution is indeed poorly characterized as being "a series of copying errors". However, organic evolution does not work by "a series of copying errors" either. Organic evolution involves recombination, mergers and changes that are not errors in addition to copying errors. So does cultural evolution.

It is odd to hear this criticism from someone knowledgeable about evolution. It's just a pure misconception about how the mechanics of evolution works. I went through this already in my "Are most words intelligently designed?" video. Is Steven Pinker on the internet? Perhaps someone can draw his attention to this conceptual problem.

It's true that intelligent design has been applied to memes - in memetic engineering. However intelligent design has been applied to genes too - in the form of genetic engineering. In neither case is evolutionary theory compromised. Cultural evolution and organic evolution remain "curiously parallel".

Memetics indeed "holds out the promise of new ways of understanding cultural and historical change". However it is far, far ahead of Stephen Pinker's understanding of it.

References

  • Campbell, Donald T. (1965) Variation and selective retention in socio-cultural evolution.
  • Campbell, Donald T. (1974) Evolutionary epistemology.

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