Wednesday 6 February 2013

Keeping Darwin in mind

A critical comment on one of my posts raises the following issue:
In A Devil's Chaplain wrote that humans (and only humans) have the gift of foresight "something utterly foreign to the blundering short-term ways of natural selection."

Utterly foreign. In the BBC Profiles video while promoting the book he said "The human brain is the only possible engine of departure from Darwinian principles, and it really is." Dawkins and Dennett (in lecture and interview) both acknowledge that humans "are the only/first intelligent designers on the tree of life." As I have said previously the question is no longer design (which evolution is the answer to) but drive. What are the causal forces that move humans, and their thought around?

The thing is, the human brain itself works on Darwinian principles. Its components use copying ubiquitously (signals are copied whenever an axon branches), and there's variation of what is copied plus selection. Ideas evolve within minds during individual learning, just as they evolve between minds during social learning. Copying, variation and selection are the basic ingredients of Darwinian evolution, according to many formulations of it - so the brain evolves along Darwinian lines.

Within-brain Darwinism was worked out by Campbell, Skinner, Changeux, Edelman, Szathmáry and Calvin - and has been popularized by Cziko, Plotkin, Dennett and myself, among others. In short, the brain is a Darwin machine.

B. F. Skinner was one of those who pioneered this view, making the analogy between Darwinian evolution and learning explicit. He used the term "extinction" to refer to the obliteration of memories - usage that persists in psychology to this day.

This within-brain evolution is a fundamental part of universal Darwinism.

No doubt the remaining critics will say that within-brain selection is deliberative selection. However, we have deliberative selection in common-or-garden evolution as well - it's called mate choice, or sexual selection. No doubt critics will say that within-brain variation is composed of directed mutations. However both evolutionary theory and Darwinism are cool with directed mutations. The various definition(s) of "evolution" typically make no mention of the source of variation, they just say that it needs to exist. As for Darwin, he understood relatively little about how variation arose. He had some theories, but largely knew that he didn't know. Directed mutations might well be contrary to neo-Darwinism, but that's a very different ball-game.

Many critics don't have a proper appreciation of the issue of Darwinian evolution within the brain. They think that intelligent design represents a radical departure from evolution. What they don't grasp is that the brain evolves at high speed, and its productions are the result of many generations of reproduction, variation and selection of signals and ideas. Brains are a neat invention, but they still work on evolutionary principles.

Also, for many years, most of the researchers in cultural evolution didn't understand within-brain evolution either. The individual learning folk and the social learning folk came from different disciplines - and it took a while for them to find each other, swap notes and get onto the same page.

Here's an example of this misunderstanding in action among researchers generally sympathetic towards an expanded domain for Darwinism:

A number of other nonselective processes may affect the evolution of ideas. For example, people can learn an idea from others and then innovate, modifying the idea in an effort to improve it. Still other nonselective processes can arise when people synthesize their own beliefs after being exposed to a number of people who behave differently.
Here learning and critical evaluation are described as being "nonselective processes" - when it is now evident that any proper understanding of them would involve considerable quantity of selection between ideas inside minds.

Today, understanding of within-brain evolution lags behind understanding of cultural evolution - which itself remains poorly understood. Universal Darwinism is an even-less-well-understood fourth stage in the evolution revolution.

As for the idea that "humans (and only humans) have the gift of foresight", that is just daft. All animal brains forecast the future consequences of their actions, in order to allow them to choose between them. That's the basis of the memory-prediction framework.

Lastly, it is Darwinian evolution within the brain that represents the primary conceptual link between evolutionary theory and machine intelligence.

References

Posted by at
Labels: ,

6 comments:

  1. Anonymous6 February 2013 at 20:03

    As for the idea that "humans (and only humans) have the gift of foresight", that is just daft. All animal brains forecast the future consequences of their actions, in order to allow them to choose between them. That's the basis of the memory-prediction framework.

    That was what you said in relation to Dawkinsk own words. Our entire legal system is against you on that point Tim. Every day we hold humans to account for their actions in a way we don't of particles, plants and animals.

    You can't have it all ways here. If genes are the seat of structure for action, and animals, plants and particles react with instinct, even reflex then that is not "choosing" that is doing. The alternate state is to act independent of environment and such atomism doesn't exist anywhere in the universe. There is always some kind of dance between the internal and external, and the human mind is a game-changing emergence from the evolutionary process that allows us to create art, to create technology (animals can't even make a compound tool) and to design and create a new dimension of phenomena:the socialworld of humankind, cities and the urban with culture, not nature the system ebbing and flowing through it.

    Are you saying that animals have the ability to choose between behaviours to the level where we can hold them to account for their actions? Are you saying that other species are free to choose and we should hold them legally accountable for their actions, not just humans? It's an important question because it gets right to the heart of not only selection, but being a selector.

    ReplyDelete
  2. Anonymous6 February 2013 at 20:35

    However both evolutionary theory and Darwinism are cool with directed mutations. The various definition(s) of "evolution" typically make no mention of the source of variation, they just say that it needs to exist.

    Again, your words above. This is the stuff of delusion now from you. Evolutionary theory and even moreso Darwinism are not cool with directed mutation. Evolutionary theory can argue it is a highly non random process but it requires:
    1. Random mutations, if the mutations are directed then that is Lamarckism "the inheritance of acquired characteristics" and not Darwinism. It is alarming that you are cool with the idea that evolutionary theory is 'cool' with directed mutation. The current work on protogenes and epigenetics penetrates the Weismann barrier and these 'microLamarkian processes' are alarming findings for neoDarwinians, who are not cool with Directed Mutations. Dennett even called Lamarck one of his three losers in 'Darwin's Dangerous Idea'

    2. Reference to 'the various definitions of evolution' almost opens the door to you using Lamarck to defend your position of Universal Darwinism. You're in good company here Dennett's 1999 'Evolution of Culture' lecture involves an inversion of history to the point where he tries to make out Lamarck was a Darwinian (after calling him a loser previously in 1996). Lamarck (or rather neo-Lamarckism) undermines the entire Universal Darwinian effort or attempt. Not all change is Darwinian and ultimately that is what you are arguing, in the face of evidence that says something quite different.

    If it was all as simple as copying, variation and selection then we wouldn't have needed Darwin/Wallace, we'd have stopped at Lamarck, or even earlier. We didn't and I'm glad because now we know that random mutations over incredibly large stretches of temporal sequence can result in change(s) that can all be preserved or in face of competition, or from human selectors can be selected for/against.

    All to often your position refers to evolution(s) and then generalises away from Darwinian theory only to return to the dogma that is Universal Darwinism, the neoDarwinian equivalent of Intelligent Design, only your position is UD, not I.D.

    I.D. Is all about 'intelligent design' and we can characterise the wordy attempts to legitimise UD as intelligent define. It has failed to gain any traction in cosmology despite Lee Smolin's work and despite you saying that you and others have worked it out the world of neuroscience doesn't Neural Darwinism is the answer to a theory of mind.

    Evolution is a kind of change in the nature setting and it was worked out by naturalists. In the physical world there are different processes of change, different phenomena, indeed it is a different dimension of causality. The human world emerges from the evolutionary process as 'the world of meaning' (not memeing) in the words of Dennett himself, and we can try and work out the underlying laws, mechanism and even equation or we can cut and paste a simple misunderstanding from one domain (nature in this case) and "slap it on another domain" (in the words of Richard Lewontin). That doesn't work Tim, and it hasn't worked to date. Universal Darwinism might well work for you but what you have is largely a literary portfolio of terms and more terms. That is not science, it's more akin to pseudoscience. Like I said before: intelligent define.

    ReplyDelete
  3. Tim Tyler7 February 2013 at 03:21

    I already explained that neo-Darwinians not being cool with directed mutations is a whole different topic. Evolution is agnostic about the source of variation. Check with the definition of "evolution" in the evolution textbooks if you don't believe me. If someone genetically engineers their kid, that still counts as evolution - since it changes the populations gene frequencies. As for neo-Darwinians - it doesn't really matter much what neo-Darwinians thought because "The modern synthesis is toast" - http://on-memetics.blogspot.com/2011/10/modern-synthesis-is-toast.html

    ReplyDelete
  4. Tim Tyler17 February 2013 at 13:48

    I fact-checked and found: "Chimpanzees are experts at using compound tools such as wedge stones, which are placed underneath wobbly rock anvils to create stable pounding surfaces." I don't think the idea that only humans can make compound tools is correct.

    ReplyDelete
  5. Unknown5 February 2014 at 13:43

    What you are doing there (and you are not alone) is that you are 'clumping' vast swathes of phenomena under the rather simple term 'tools' and that completely over-rides the difference between proto-tools and advanced technology. That is a political strategy and not one that should take hold in science. If you take your line of enquiry there is no need to generate a theory of culture that explains why we have a rover on Mars, or an international space station, or defibrilators so that when nature says "no", humans can say "yes". If you take all that vast disparity and file it under 'tools' that is clumping pure and simple and has no place for people who want to critically think through the world around them.

    There has never been another species that has built a compound tool with the complexity threshold of a moving part or joint.

    I'm not the mad raving and ranting of a sole mind here, easy to discard. Michael Gazzaniga, noted neuroscientist from his edge.org article on 'Are Human Brains Unique'?

    "And while we can use lathes to mill fine jewelry, and chimps can use stones to crack open nuts, the differences are light years apart."

    So, here we have a scientist and a respected one at that objectively looking at what chimps do, and what humans do and calling the increment of difference "light years" and you without barely batting an eyelid, file it all under 'tools' (slapping hands) job done.

    What you are engaged in is word play, pure and simple. Chimps have been on the go for at least 6 millions years and they haven't made a compound tool. Behaviourally modern humans have been on the go for 40,000 years and they have a rover on Mars beaming pictures back to earth. The physical world has 95 particles and human creativity has created another 20. We can wonder at that process and try to find the real mechanism, laws and even equation for that process or we can say "Mmmmmeeeh, it's all tools." With that attitude, it's not just Memetics that has and will continue to suffer, its all the schools of thought that try and Darwinise culture. For them culture can't be different in dimension from nature, and we know that artificial and synthetic are what the human social world are all about, but not the natural world.

    The carousel is slowing on this cultural bandwagon of clumping, and knowledge and science are moving on as we seek something altogether more satisfying and not more inert narrative and pseduo-science Tim. You're interested in culture and that is a good thing, but at some point you took the wrong turn off marked 'Memetics' and that is a dead end in terms of the general theory of culture that truly pulls together the social sciences, arts and humanities.

    ReplyDelete
  6. Tim Tyler5 February 2014 at 17:51

    That's quite a rant about the definition of "compound tool"!

    Scientifically speaking, I don't think you have a leg to stand on. Here's another example:

    "A compound tool consists of two or more component tools are combined into a single device. An example of a tool composite used by chimpanzees is a leaf sponge. A leaf sponge is made from several fresh leaves that are combined to form an absorbant clump. The clump is used by the chimps to extract water from crevaces such as tree holes."

    ReplyDelete

Subscribe to: Post Comments (Atom)