Transcript Morality - University of Alberta

Psychology 485
March 30, 2010
 Introduction
& Philosophy of Morality
 Group Living & Cooperation
• Altruism
• Game Theory
 Moral
Instinct?
• Ultimatum game
• Fairness and empathy in animals
“the difference in mind between man
and the higher animals, great as it is,
certainly is one of degree and not of
kind”
• Darwin, The Descent of Man
"Of all the differences between man and
the lower animals, the moral sense or
conscience is by far the most important"
• Darwin, The Descent of Man
 Some
Traditional Answers:
• Reason
• Experience
• Religion/God
A
newer answer:
• Moral Instinct
 Morality
springs from
reason
 Categorical Imperative
• Only acts that can be
universally permissible (and
thus expected) can be taken
 Morals
(or moral
problems) excite emotion
 Emotions cause behaviour
• Reason has nothing to do
with it
 How
are ethics grounded in the natural
world?
• Evolution & Biology?
• e.g. Westermarck effect
 Need
to avoid naturalistic fallacy
• What is in nature is what “ought” to be
• e.g. eugenics
 In
psychology, general perspective has
been to break morality into stages
 Successively
more sophisticated
reasoning
• Piaget: 3 stages
• Kohlberg: 6 stages
 Downsides:
• More conspicuous to predators
• Foraging competition
 Upsides:
• Shared vigilance for predators
• Group defense
• Cooperation and Reciprocation
• Information sharing
 Does
living in a group require a code of
ethics?

Functional definition:
• Acting in a way to
reduce individual
personal fitness, but
increase overall fitness
of group

Examples:
• Alarm calling
• Food sharing
• Adoption/sharing
parenting
• Grooming
 Altruism
explained
through genetic
relatedness
• Inclusive fitness
 “Selfish
Gene”
• Helping out family members
helps your genes get passed
on
 Rescue
behaviour in ants
 Altruism
in non-kin
 Expectation of
‘returning the favour’
 Detection of
cheaters?
• Would behaviour evolve
cheating was common?
 Tit-for-Tat
strategy
 Mathematical
approach to
multi-agent interaction
• Specifies what agents should do to
maximize their payoffs against
rational agents
 Nash Equilibrium
• Stable solution to game theoretic
problems
• Evolutionary stable solution (ESS)

2 suspects caught by
police
• Cooperate (stay silent)
• Defect (testify against
other guy)


Players should always
defect
Nash equilibrium does
not equal globally
optimum solution
 Can
cooperation be elicited if game is played
multiple times?
 If
total number of trials is known, continue to
defect
• Should defect on last trial, since no opportunity for other
player to “punish”
• If both will defect on last trial, should defect on 2nd last…
etc.
 If
total number of trials is not known, defection
may not be dominant strategy
• Tit-for-Tat: Cooperate, then copy

Studies show that animals
tend to defect, even in
iterated problems
• Temporal Discounting?

Stephens, McLinn &
Stevens (2002)
• IPD with blue jays
• Food held in ‘accumulator’
to reduce discounting
• Cooperate in Tit-for-Tat
strategy
 Moral
values change with cultural & lifestyle
• e.g. smoking, working mothers, divorce, homosexuality
 Vegetarian
lifestyles:
• Health vegetarians – don’t eat meat for practical, health
reasons
• Moral vegetarians – don’t eat meat for ethical reasons
 More likely to see meat as ‘contaminant’, believe other
people should be vegetarians, associate vegetarianism
with other virtues (less aggressive)

But “instinct” or gut-feelings seem to have control:

Moral Dilemma 1a:
• A surgeon walks into the hospital as a nurse rushes forward
with the following case. “Doctor! An ambulance just pulled in
with 5 people in critical condition. Two have a damaged
kidney, one a collapsed lung and one a completely ruptured
liver. We don’t have time to search for possible organ donors,
but a healthy young man just walked in to donate blood and is
sitting in the lobby. We can save all five patients if we take the
needed organs from this young man. Of course, he won’t
survive, but we will save all five patients.”
 Is it morally permissible for the surgeon to take this young man’s
organs?
 Moral Dilemma 1b:
• A train is moving at a speed of 150 mph. All of a sudden,
the conductor notices a light on the panel indicating
complete brake failure. Straight ahead of him on the track
are five hikers, walking with their backs turned,
apparently unaware of the train. The conductor notices
that the track is about to fork, and another hiker is on the
side track. The conductor must make a decision: He can
let the train continue on its current course, thereby killing
the five hikers, or he can redirect the train onto the side
track and thereby kill one hiker, but save five.
 Is it morally permissible for the conductor to take the side
track?
 Most people:
• “no!” to question 1 (organs)
• “yes!” to question 2 (trains)
 Parallel structure, same calculus
• What’s the difference?
 Hints
at moral intuition
 Search for Universal Moral Grammar
• Parallel to language
 Cross-cultural
similarities

Julie is traveling in France on summer vacation from
college with her brother Mark. One night they decide
that it would be interesting and fun if they tried making
love. Julie was already taking birth-control pills, but
Mark uses a condom, too, just to be safe. They both
enjoy the sex but decide not to do it again. They keep
the night as a special secret, which makes them feel
closer to each other. What do you think about that —
was it O.K. for them to make love?
 Haidt (2001)
 Broken
down into 5 main themes:
• Harm/Empathy
• Fairness/Reciprocity
• Community
• Authority/Hierarchy
• Purity
 If
morality is “built-in”, based on instinct,
parts of human morality may have
precursors in animal behaviour
• Moral building blocks?
 Focus
on 2 dimensions:
• Harm/Empathy
• Fairness/Reciprocity
 Rhesus
monkeys
trained to pull a chain
for food reward
• Now response leads to
another monkey getting
shocked (in addition to
food)
 Monkeys
will go
hungry for days
 Masserman et al (1964)
 Rats
trained that
pressing a lever
lowered a styrofoam
block
 Tested with
“suspended rat”
• All rats worked to lower
the other rat
 Rice & Gainer, 1962
 Player
1 is given $100, must offer a split
to Player 2
 Player
2 can accept or reject offer
• If reject, neither player gets any money
 Rational: Accept
anything
• But, offers less that 20% are often rejected
• Why? Violates principle of ‘fairness’
 Chimp
version of ultimatum game
 Jensen, Call & Tomasello (2007)
 Must
work together to pull in food reward
 Chimps
rarely
refused offers
• Rational response
 Design
problems?
“Any animal whatever, endowed with
well-marked social instincts, the parental
and filial affections begin here included,
would inevitably acquire a moral sense
or conscience, as soon as its intellectual
powers had become as well developed,
or nearly as well developed, as in man.”
• Darwin, The Descent of Man