Chapter 10: The evolution of consciousness
- The Design Argument
- A complex piece of
machinery (like a watch) cannot have come about by accident.
- I can infer the existence of a designer from the
well-designedness of it: it must be a product of intelligent design:
- Many natural objects (from eyes to ecosystems) are complex
pieces of machinery.
- So, these objects "imply the presence of intelligence and mind"
(Paley, 1802: 13)
- So, there must be an Intelligent
Designer of nature.
- Wm. Paley: "there cannot be design, without a designer;
contrivance, without a contriver; order, without choice" s
- Evolution as "the Blind
- Richard Dawkins:
"Paley's argument ... is wrong, gloriously and utterly wrong."
- Paley's argument is that there's no other way that these
structures could come about.
- Dawkins: Darwinian
evolution -- "the blind watchmaker" -- is the other way
- Darwin's The Origin of Species
- Full title, The Origin of
Species by Means of Natural Selection or the Preservation of Favoured
Races in the Struggle for Life
- Natural Selection:
- If reproducing creatures vary (as they do).
- And the carrying capacity of environments are finite (as
- Then some variants will be more successful at reproducing
in the environment than others. (Natural selection).
- By this means those variations which are "fittest" will
"survive" (leaving more offspring) and come to be preserved.
- This leads to evolution: "the improvement of each [type of]
creature in relation to its conditions of life" (SB: 140)
- SB's speculative evolution of the eye
- In a population of creatures with single photosensitive
cells, those with more cells might have an advantage; in a population
with eye pits, those with deeper pits might do better; and so on until
eyes with corneas, lenses and foveas are forced into existence.
- Thus were Paley's eyes, etc. "designed" by evolution: "a scheme
for creating Design out of Chaos without the aid of Mind." (Dennett
- Simulations of Evolution
The Problem with Lamark
- Lamarkian evolution
- acquired characteristics are inherited
- change is inevitably progressive: directed design
- other directed evolution
- Resistance to Darwin's ideas continues to the present day in the
popular cultural arena
- Darwinism's scientific
triumph was cemented by the discover of the mechanism of inheritance
- in the 1930s the "modern
synthesis" brought together natural selection and Mendelian
- in the 1960s Crick and Watson identified Mendelian genes as DNA
- "Who or what is evolution for? Who or what is that ultimate
beneficiary of all those adaptations such as eyes, wings, and digestive
systems." (SB: 145
- The Selfish Gene
theory: the ultimate beneficiary of natural selection is neither the
species nor the group, nor even the individual, but the gene.
- genes are the replicators
- on which selection operates: "they are selfish in the sense
that they will get copied if they can" (145)
- In addition, "many features of organisms are not adaptations, or
are far from optimal if they are" (146)
- "some useless traits survive because they are by-products of
other traits that have been selected" (146)
- "Others ... because they were once adaptive and there has not
been sufficient time to weed them out." (146)
- "Contrary to popular belief, the gene-centered theory of
evolution does not imply that
the point of all human striving is to spread our genes ... People
don't selfishly spread their genes; genes selfishly spread
themselves. They do it by the way they build our brains. By
making us enjoy life, health, sex, friends, and children, the genes buy
a lottery ticket for representation in the next generation, with odds
that were favorable in the environment in which we evolved." (Pinker
- Evolutionary psychology 'treats
the human mind as a collection of specialized modules, or information
processing machines, that evolved to solve particular problems"
- the "Swiss army knife" view of the mind
- invokes the fact that we are evolved hunter-gatherer lives on
the African savanna to explain traits that are now maladaptive (e.g.,
craving for high-fat foods)
- Pinker on the hard problem: "Beats the heck out of me!"
Consciousness in Evolution
- Evolutionary answers to why questions
- Why are leaves flat and green? The better to
- Why do cats have fur. To retain body heat.
- Why do birds have wings? In order to fly.
- So why are we conscious?
- So we can what?
- What's the function
- Problem for the evolutionary explanation of consciousness
- unless it's a "spandrel" .. perhaps this would be the
epiphenomenalist evolutionist's story
- "either we throw away the idea that consciousness evolved by
natural selection, or else we have to find a function for it."
(Humphrey, 1987: 378)
- Those who deny consciousness evolved
- "some Christians and Muslims believe that each of us has a soul
created by God, and that consciousness is a property of that
soul. So they do not believe that consciousness evolved."
- [Note the conclusion does not follow: perhaps evolutionarily is
how God creates souls.]
- Difficulty with its evolution of consciousness
- intuitively, we can understand the survival value of
intelligence, memory, perception, etc.
- what's the further advantage of the light of consciousness
- "It is conceivable that evolutionary processes could have
worked to build creature as efficient and intelligent as we are ...
without those creature being subjects of experience." (Flanagan, 1992:
- In other words, "it is hare to explain why evolution produced
us instead of zombies." (Moody 1995: 369)
- "The process of natural selection cannot distinguish between me
and my zombie twin" (Chalmers, 1996: 120).
- "If such a [consciousness inducing] mutation were possible, then
it would be entirely, and necessarily, neutral, and would make not
difference at all to the way these creatures evolve." (SB: 150)
- Three alternatives
- Conscious inessentialism
- Zombies are possible.
- Consciousness is separable from adaptive behavior.
- Problem: how would it evolve?
- Consciousness has a function
- Zombies are not possible.
- Consciousness is separable from evolved adaptive
traits. It adds something new functionality.
- The problem for this approach is to say what this new
- Functionalism: high-level
intelligent abilities have to be conscious.
- Zombies are not possible.
- Consciousness is not separable from evolved adaptive traits
such as language, memory, and problem solving.
- The problem for this approach is to say why such adaptive
traits should require subjectivity..