Evolution Sees!

Synopsis

This essay argues against the notion that evolution is a blind process with no foresight.

The blind watchmaker

The argument that the evolutionary process is blind has been made by many - notably Dawkins:

Paley's argument is made with passionate sincerity and is informed by the best biological scholarship of his day, but it is wrong, gloriously and utterly wrong. The analogy between telescope and eye, between watch and living organism, is false. All appearances to the contrary, the only watchmaker in nature is the blind forces of physics, albeit deployed in a very special way. A true watchmaker has foresight: he designs his cogs and springs, and plans their interconnections, with a future purpose in his mind's eye. Natural selection, the blind, unconscious, automatic process which Darwin discovered, and which we now know is the explanation for the existence and apparently purposeful form of all life, has no purpose in mind. It has no mind and no mind's eye. It does not plan for the future. It has no vision, no foresight, no sight at all. If it can be said to play the role of watchmaker in nature, it is the blind watchmaker.

However, the idea is not really correct. It is a mischaracterisation of the evolutionary process. As a metaphor, it is fundamentally misleading.

Evolution waking up

Evolution can be characterised as a process of iterative reproduction with variation and selection.

When evolution started, it really did deserve the "blind" moniker - both variation and selection lacked vision and foresight.

However, after a while, sensors and eyes evolved, and then the process of selection was able to work with observations of the world. After that, brains evolved. The main function of brains is predicting the future - so that organisms may understand the consequences of their possible actions - so that they may choose between them.

With the advent of brains, the selection process literally involved making predictions of the future - due to the process of sexual selection in which female choice decides which genes survive, and which do not. For many of our ancestors, intelligence was a fundamental part of female choice - not an incidental aspect of it. Who to mate with is an important and difficult decision for many females, and their intelligence is definitely engaged in the process.

The next major development in the mechanics of evolution was the development of engineers, and intelligent design. That introduces vision, intelligence and foresight into the process of variation.

With that development, the symbolic representation of the process of evolution now looks like this:

Formal Blindness

Dawkins uses the term "blindness" rather metaphorically - and it's possible to claim that his use is too vague to be incorrect. However evolutionary "blindness" has been championed in recent times by Donald Campbell - and he means something specific by it.

Campbell argues that even scientists and engineers are blind.

In going beyond what is already known, one cannot but go blindly. If one can go wisely, this indicates already achieved wisdom of some general sort [...] which limits the range of trials.

This idea involves a redefinition of the term "blindness".

As Cziko says:

But we must be careful to make clear what is meant by blind in this context. First, blindness does not imply that all variations are equally probable. For this reason, the word random is probably not a suitable descriptor since to some it may carry that connotation. Second, blindness does not mean that the process of producing variations of ideas, theories, and experiments for testing is necessarily unconstrained. Our superconductivity-seeking scientist is not likely to throw just anything into her concoction of chemicals, such as some of last night's leftover soup. Instead, she will rationally try out those substances in those proportions and under those conditions that, based on her knowledge of previous research and current theory, she believes have the greatest chance of success.

So it cannot be denied that previously achieved knowledge has an important role to play in constraining the variations to be investigated. Nonetheless, the new concoction is still a blind variation in the sense that the scientist does not know, and cannot know, if the resulting material will be an improvement over previous ones. It is in this important sense that the variation, although far from random and unconstrained, remains blind. The manner in which you grope about in a dark room to find the light switch changes significantly after making contact with the wall on which the switch is located. What were three-dimensional gropings now become two-dimensional ones. And as you encounter the molding along which you know the switch is located, your gropings become further constrained to just one dimension. But although they may become progressively and usefully constrained over time, an unavoidable blind component exists in your gropings until you actually find the switch.

The idea here is that any lack of knowledge is blindness.

Conventionally, blindness means not being able to see anything. But Cziko and Campbell are redefining the term blindness to mean: not being able to see at least one thing.

This is henious abuse of terminology, in my book. Taking a common, well-known word and giving it a technical meaning which totally contradicts the standard usage in almost every context is not a smart move.

Cziko's example of a man in a dark room seems designed to mislead. Likening a man groping in a darkened room to someone who is blind sounds reasonable. However the man finds the switch because he has other ways of sensing besides vision - an idea which totally violates the spirit of the analogy between vision and the seeking of knowledge. To preserve that analogy, the man should have stumbled across some matches - and then located a torch - before finding the light switch. Of course, then the idea that the man with the torch was "blind" would sound totally ridiculous.

Astronomers are not "blind" because they cannot see the far side of the moon. Ornithologists are not "blind" because they cannot observe the behaviour of the Dodo.

"Blindness" does not mean that there is something you cannot see. It means that you cannot see anything.

Scientists are not "blind". A sensible term would be "not omniscient": scientists are not omniscient. If you want to stick to a visual metaphor, they are not all-seeing. The notion that they are blind is a ridiculous one.

Component composition

What about the idea that wholes do not necessarily display the properties of their components? A box of red and shiny toys is not necessarily itself red and shiny. A flock of seagulls does not have legs and a beak. So why should evolution as a whole exhibit foresight simply because it is partly composed of intelligent organisms who can predict the future?

The trait we are talking about is foresight - the ability to predict. What if all organisms made different predictions, and the results cancelled out? It is not hard to imagine something like this happening: when squirrels on one side of the planet preparing for sleep, squirrels on the other side are waking up; when squirrels on one half of the planet are busy preparing for winter, squirrels on the other half are celebrating the coming of spring. Don't most predictions of meteorological cycles - which are an important thing which organisms need to predict - actually cancel out?

This is like arguing that the meteorological office can't predict the future because it predicts all types of weather all the time - but in different places. You cannot average together predictions of snowing in England and Australia - those are different predictions.

In practice, a great number of individuals predicting events normally do a lot better than any individual manages - so evolution can be expected to predict the future rather well.

Weakness

How about the idea that predictions by intelligent agents are not the only force present in evolution, and they do not represent a very strong force - and so any resulting effect is typically swamped by other factors.

This seems like a not-unreasonable objection for the early history of life - though probably the effect of intelligence would be diluted, rather than eliminated.

However, with the rise to dominance of the planet by brainy organisms, this case has become increasingly difficult to make. In the case of modern humans, we may not be in complete control of the path evolution takes - but at least we have a significant say in the matter - and, for example, if we see a meteorite coming Earth's way, a significant fraction of the planet's resources can be mobilised in defense.

Materialistic blindness

What about the claim that physics consists of inanimate molecular interactions and thermodynamics means that past events cause future ones, and material causation has no foreknowledge?

This is of course correct - but I don't think this type of lack of foreknowledge is what most people who say evolution is "blind" mean.

For example, Dawkins says evolution "does not plan for the future". There is nothing about planning for the future that contradicts materialism. If evolution featured an " invisible sky-daddy" - who got to decide who lived, who died, and who reproduced - the claim that "evolution is blind" would be widely recognised as being wrong - even if the selective agent in question followed the material laws of the universe, and had its actions determined by past events.

So, the idea that causal laws always use past events to predict future ones is trivially true - but it should not be seen as the basis of the idea that evolution is blind.

Other interpretations

I have not seen it argued, but possibly it might be claimed that the term "evolution" does not refer to the process associated with the term, but rather to the abstract idea of the iteration of variation and selection. The idea being that you can abstract the ideas of selection and variation away from the mechanics of the processes that are performing those tasks. If you do that then evolutionary blindness becomes trivially true - simple, abstract ideas cannot possibly make predictions or have foresight.

However, as far as I can tell, nobody who defends the idea of evolutionary blindness has ever actually adopted this position. Proponents are all promoting the idea that the evolutionary process is blind to the future. They literally think that evolutionary systems cannot make plans or anticipate future developments.

Evolution is not blind

Evolution is not blind. Brains and sexual selection introduced intelligence into the selection process. Engineering introduced intelligence into the process responsible for the production of variation.

Evolution was blind in the beginning. Back then, the metaphor of a blind idiot god would have been an appropriate one. However, as with the development of animals, it has gradually acquired the power of sight. With the origin of brains, evolution turned into a kind of cyclops god with partial vision. Now, with the origin of engineers, evolution can now see even more clearly.

To think of the process of evolution as a blind process is an impoverished view, which represents a fundamental misconception of its character.

Human beings are largely the product of choices by intelligent agents, capable of predicting the consquences of their actions, and are not - in any reasonable sense - the product of "blind" selective forces.

References

  1. Richard Dawkins - The Blind Watchmaker, 1982;
  2. Donald Campbell - Evolutionary Epistemology, In The philosophy of Karl R. Popper edited by P. A. Schilpp, 1974, p. 442;
  3. Gary Cziko - Without Miracles;
  4. Daniel Dennett - Darwin's Dangerous Idea;


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