Transcript Morality_and_Evolution

Evolution and Morality
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Outline
Introduction
Problem 1: How could morality be the result of evolution?
Problem 2: Morality debunked?
Conclusion
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Introduction
Evolution and Morality
P1. Human behavior is the result of evolutionary forces
P2. Human beings behave as moral agents
CC: Moral behavior is the result of evolutionary forces
 We should be able to explain human moral
behavior in terms of evolutionary forces
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Introduction
Two Problems
PROBLEM 1:
P1: The law of evolution is a law of competition
P2: Moral behavior includes seemingly non-competitive
behavior – cooperation, altruism, sacrifice
CC: Evolution cannot explain moral behavior
 If evolution is a matter of competition, how could
moral behavior have been selected?
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Introduction
Two Problems
PROBLEM 2:
P1: Evolution explains human behavior in terms of
biological processes which are determined and have
no “truth” to them
P2: Moral behavior properly speaking is free and has value
only if it based on truths
CC: “If evolution is right, then there is no moral behavior
properly speaking”
 If moral behavior is the result evolution, is not
morality an illusion?
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Outline
Introduction
Problem 1: How could morality be the result of
evolution?
Problem 2: Morality debunked?
Conclusion
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How could moral behavior result from
evolution?
PROBLEM 1:
P1: The law of evolution is a law of competition
P2: Moral behavior includes seemingly non-competitive
behavior – cooperation, altruism, sacrifice
CC: Evolution cannot explain moral behavior
THREE ANSWERS:
1. Moral behavior as a side effect
2. Biological Altruism
3. Selection of cooperative behavior
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1. Moral behavior as a side effect
Non-adaptive traits as a side effect:
- The development of the human brain is the result of
evolution
- Moral behavior comes as a non-adaptive side effect
Other Examples:
- Nerdy behavior
- Taste for sweets and fats
 Moral behavior could be a non-adaptive side effect
of the development of the brain
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2. Biological Altruism
Biological altruism
- Reciprocal aid
- Kin selection
Other Examples:
- Vervet monkeys’ calls
- Insect colonies
 Human moral behavior could be a case of
biological altruism
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3. Selection of cooperative behavior
The Problem:
Prisoner’s dilemma
Jones cooperates
Jones defects
Smith cooperates
Jones: 3
Smith: 3
Jones: 5
Smith: 0
Smith defects
Jones: 0
Smith: 5
Jones: 1
Smith: 1
Simulation type 1:
- Single encounter:
- Best strategy: defect
- Paradox: both lose in trying to win!
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3. Selection of cooperative behavior
Simulation type 2:
- Repeated encounters
- Memory of past encounters
- Best strategy: Cooperate
 Cooperative behavior selected in the long run
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How could moral behavior result from
evolution? -- Conclusion
PROBLEM 1:
If the law of evolution is a law of competition, could moral
behavior, including cooperation, altruism and
sacrifice, be selected?
ANSWER: Of course.
Cooperative behavior, altruism and sacrifice can be the
most competitive behavior in certain environments.
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Outline
Introduction
Problem 1: How could morality be the result of evolution?
Problem 2: Morality debunked?
Conclusion
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Morality debunked or strengthened?
Steven Pinker of Harvard University:
“… dissecting moral intuitions is no small matter. If
morality is a mere trick of the brain, some may fear,
our very grounds for being moral could be eroded. Yet
as we shall see, the science of the moral sense can
instead be seen as a way to strengthen those grounds,
by clarifying what morality is and how it should steer
our actions"
 Pinker: Morality not debunked but strengthened.
How?
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Morality debunked or strengthened?
Two Arguments
1. Argument for Determinism:
P1. If our moral behavior results from our biological make
up, then it is determined.
P2. Moral behavior is true moral behavior only if it results
from free will
CC. There is no true moral behavior -- illusion
 Are we biologically determined to make the “moral”
choices we make?
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Morality debunked or strengthened?
Two Arguments
2. Argument for Relativism:
P1. Whether a trait is selected by evolution depends on
whether or not such trait is beneficial to survive in a
certain environment.
P2. Whether or not such trait is beneficial to survive in a
certain environment has nothing to do with it being
right or wrong
CC. If our moral behavior is a trait selected by evolution,
then it has nothing to do with right or wrong, ie:
- moral behavior is not grounded in moral truths
 Is our “moral” behavior just another mean to
survive?
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Morality debunked or strengthened?
Against the Argument for Relativism
Is our “moral” behavior just another mean to survive?
Compare with mathematics:
- We are born with a evolutionary-driven rudimentary
mathematical knowledge - monkeys have this too.
- We build on it with mathematical reasoning and discover
mathematical truths
 From the fact that a rudimentary version of our
mathematical knowledge is the result of
evolution, it follows that we can build
autonomous, true knowledge.
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Morality debunked or strengthened?
Against the Argument for Relativism
Then for morality:
- We are born with a evolutionary-driven rudimentary
moral tool-kit
- We build on it with rational reasoning and discover moral
truths
 There is no reason to reject the idea that that there
are moral truths if we admit the existence of
mathematical truths
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Morality debunked or strengthened?
Conclusion
Evolutionary forces explain rudimentary versions
some of our tendencies toward moral behavior,
and some of the content of our moral thoughts.
But evolution is not the whole story:
- There is no determinism of moral behavior
- From the fact that some rudimentary version of
morality is the result of evolution, it does not
follow that there are no moral truths
 Autonomous rational thinking is what makes moral
behavior and moral thoughts truly moral.
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Conclusion
Steven Pinker:
"Far from debunking morality, then, the science of the
moral sense can advance it, by allowing us to
see through the illusions that evolution and
culture have saddled us with and to focus on
goals we can share and defend. As Anton
Chekhov wrote, “Man will become better when
you show him what he is like.” "
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