The emperor’s new paradigm - Budapest University of

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Transcript The emperor’s new paradigm - Budapest University of

The emperor’s new
paradigm
The rise and fall and rise and fall
of evolutionary perspectives in
psychology
On evolution
A chicken is just an egg's way of
making more eggs.
Charles Darwin
 Premise 1: Struggle for survival
 Premise 2: Variability
 Premise 3: Heritability
 Premise 4: Fitness
 CONCLUSION : NATURAL
SELECTION
•He observed breeders and different naturally evolving
species
•Charles Babbage: God = programmer of laws
Charles Darwin
 Premise 1: Struggle for survival
 Premise 2: Variability
 Premise 3: Heritability
 Premise 4: Fitness
 CONCLUSION : NATURAL
SELECTION
 (Artificial selection = eugenics – later!)
On the origin of species, 1859

Premise 1: Struggle for
survival



Species have great fertility.
They have more offspring than
ever grow to adulthood.
Populations remain roughly the
same size, with small changes.
(Food resources )
An implicit struggle for survival
ensues.
On the origin of species, 1859

Premise 2: Variability


In sexually reproducing species,
generally no two individuals are
identical.
Some of these variations directly
affect the ability of an individual to
survive in a given environment.
On the origin of species, 1859

Premise 3 Inheritability

Much of this variation is
inheritable.
 Mind you: Mendel’s work –

though existant at the time
– was not known by Darwin
from the outset!
Inheritance mechanism
was imagined entirely
differently
On the origin of species, 1859
 Premise 4


Fitness
Individuals less suited to
the environment are less
likely to survive and less
likely to reproduce,
while individuals more
suited to the environment
are more likely to survive
and more likely to
reproduce.
On the origin of species, 1859

CONCLUSION : NATURAL
SELECTION

The individuals that survive
are most likely to leave their
inheritable traits to future
generations.

A continuous natural
embetterment of the world?
Underlying assumptions
 Premise 1: Struggle for survival
 Malthusian idea – technological improvement
 Premise 2: Variability
 Much uniformity
 Premise 3: Heritability
 Debates even today – syphilis, doctoritis running
in families
 Premise 4: Fitness – well-adapted to the
environment
 Not at all a clear concept
 Sickle cell anaemia
 what it means for a non-natural selection
philosophy
The puzzling survivor
 The Naked Ape – homo sapiens
 No claws
 No sharp teeth
 Not too fast – slower than most predators at
any rate
 Why is this parody of evolutionary
perfection still around and moreover
everywhere?
Solution by Evolutionary
Psychology
 The adapted mind
 The complexity seen in nature by Darwin
is compared to the complexity in human
behaviour and it is explained as such
 Evolutionary psychology as an approach
Evolutionary psychology
 The Human Animal (Sociobiology)
 Adaptationism
 Originally applied to biological organs – the most wellknown is the eye
 Extensions: the brain is a biological organ
 Supposition: the brain produces behaviour and
consciousness
 Therefore: behaviour and consciousness is formed by
evolution just as the biological body is
 Eye’s complexity – in the centre of debates
Richard Dawkins
 An ardent proponent of adaptations
- earning him the title of Darwin’s
Rottweiler (and equally ardent
opponent to creationism )
 The Blind Watchmaker – focuses
on how evolution could create
marvellous structures – like the eye
 William Paley – a watch presupposes
intelligent design because of its
complexity
The Weasel problem
 Shakespeare’s Hamlet
 Hamlet: Do you see yonder cloud that's almost
in shape of a camel?
Polonius: By the mass, and 'tis like a camel,
indeed.
Hamlet: Methinks it is like a weasel.
 Based on the infinite monkey theorem
 A monkey bashing away at random on a
typewriter – given enough time he would
type the entire works of Shakespeare
 how long would it take him to produce the
sentence ‘Methinks it is like a weasel.’?
The Weasel problem
 Methinks it is like a weasel
 This is 28 characters
 Using 26 letters – only capitals and a
space bar
 Probability?
 2728 = 1040 = infinity, or at least much
longer than milliseconds from the
existence of the universe (13,73 billion =
13,73 * 109 years = 7,22 * 1018
milliseconds)
Sir Frederick Hoyle
 „approximately the same order of
magnitude as the probability that a
hurricane could sweep through a
junkyard and randomly assemble a
Boeing 747.”
 solar system full of blind men solving
Rubik's Cube simultaneously.
 The simplest bacterium needs 1040,000
permutations, while the number of the
atoms in the universe is „only” 1080,
 the chance is the same as throwing
50000 sixes in a row with a die
Sir Frederick Hoyle
 Astronomer and sci-fi writer
 He opposed the Big Bang theory –
because it needs a cause Steady
State theory
 He also opposed natural
abiogenesis!
 Intelligent design - Evolution from
Space
Hoyle’s fallacy
 You don’t need 28 letters. You start with say 3.
 They calculate the probability of the formation of a "modern"
protein, or even a complete bacterium with all "modern"
proteins, by random events.
 This is not the abiogenesis theory at all – it starts with VERY
SIMPLE organisms
 They assume that there is a fixed number of proteins, with fixed
sequences for each protein, that are required for life.
 They calculate the probability of sequential trials, rather
than simultaneous trials.
 Changing one at a time – mutations are rare but do not exclude
each other
 They seriously underestimate the number of functional
enzymes/ribozymes present in a group of random
sequences – only one good solution fallacy
The Weasel problem
 Cumulative selections instead of a single step
selection
 Two differences in his model:






 Copying mechanism – it retains previous states
 There is an inherent goal – any change that occurs
towards methinks it is a weasel is kept, others are
discarded
Generation 1: WDLMNLT DTJBKWIRZREZLMQCO P
Generation 2: WDLTMNLT DTJBSWIRZREZLMQCO P
Generation 10: MDLDMNLS ITJISWHRZREZ MECS P
Generation 20: MELDINLS IT ISWPRKE Z WECSEL
Generation 30: METHINGS IT ISWLIKE B WECSEL
Generation 40: METHINKS IT IS LIKE I WEASEL
 Generation 43: METHINKS IT IS LIKE A WEASEL
Adaptive landscapes
 Fitness or adaptive
landscapes – genetic
variation is pushed to the
direction of the arrows
 Waddington – epigenetic
landscape – curiously posits a
rolling, not a climbing ball
 Saddle points in
mathematics as nonoptimal solutions
Cosmides & Tooby
 Flexibility – a basis never questioned
 Instinct vs reason distinction
 Please make a mental note as this is to be relevant to the
discussion on implicit/explicit!
 What is instinct blindness according to Williams
James?
 Make the „natural seem strange” program
 „’of course’ is no longer a good answer” – does evolutionary
psychology manage to get round the problem?
 „cognitive psychologists spend more time studying
how we solve problems we are bad at” – the concept
of „difficult” is being redefined
The Blank Slate
 The Standard Social Science Model (SSSM)

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
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


learning
Induction
Intelligence
Imitation
Rationality
the capacity for culture
Culture
 A proposed problem with domain generality: if
there is no inborn mechanism at all (only
perception), what learns how to learn?
SSSM

What is this „roughly” supposed to mean
exactly?
Hypotheses and problems:
The problem of innateness – is it
 Babies are
born
with the same capacities
presence at birth?
(roughly) all
over the world
 YET they come to be very different adults finally, with
Are domain-general
learning
different customs
and habits
mechanisms good enough to deal with
 The differencethe
must
therefore
information
load? lie in their experience
of the world+Consider the visual system
 This experience is mediated through generalpurpose-learning Are
mechanisms
cultures all that different?
 Culture must
How much universality lies under the
be
thediffereces
explanation
– it has
cultural
of human societies?
overarching and all-pervasive effect
an
Arguments against
 Many things are not present at birth that are
rarely doubted to be innate
 Do we learn to grow beards and menstruate?
 The nature/nurture dichotomy is not only
arbitrary – it is false
 again connected to innateness
 In some cases domain-general learning
mechanisms are just not enough
 Most prominent example is language – poverty of
stimulus argument
 Moreover: striking differences - species-specific
learning mechanisms (also consider phobias)
Asking the wrong questions
 genes vs environment
~ engine or gasoline?
~ the ingredients of bread
 Presence at birth is not required – points
at the problematics of „innate”
Innateness
 What do we mean by innate? Cognitive science
 Non-acquisition
 UG – vacuous, as in a sense everything is acquired at some
point – a blastula has no UG
 Presence at birth – inborn
 Neither necessary (pubic hair), nor sufficient (prenatal
learning is possible)
 Internally caused as opposed to environmentally
induced
 Jeffrey Ellman: rethinking Innateness „the product of
interactions internal to the organism…”
 Impossible: without maternal blood, no organ could possibly
develop at all
 Triggering is often evoked – yet unsure in meaning
Innateness
 What do we mean by innate? Biology
 Genetically determined?
 Genetically caused
 Genetically represented – mapped in DNA
 Both accounts fail because of
 interactionist explanations
 difficulty of observation
 Invariance accounts – stable across „normal”
environments
 Attractive as it explains stability and universality in
a species
 YET: the concept that water is wet would be innate
Innateness
 What do we mean by innate?
 Innateness as high heritability
 Heritability=overall phenotypic variation that is due to genetic
variation (Vg/Vp)
 However: only works if there is phenotypic variation – if there
is none, it is useless
 Opposable thumb in humans – drug taaken by mother
disrupting its development -> low heritability
 Not learned
 Learning is nearly as slippery as innateness is…Yet..
 Psychologically primitive
 Can not be explained by general psychological mechanisms
– have to retreat to biological explanations
 Bootstrapping-type learning – learning that is faster that would
be expected based on a domain-general view
Adaptive minds
 Problem-specificity:
 The brain is a naturally constructed computational system whose
function is to solve adaptive information-processing problems
 Modularity of mind – the Swiss army knife model
 face recognition, threat interpretation, language acquisition, or
navigation
 Domain specificity (environment specifity) – domain generality
(modus ponens works in all environmental conditions)
 adaptive problems
 Permanent to be solved in the life of a species
 Enhance reproductive success
 What about survival?
 The side-effect trick (exaptation)
 Walking and skateboarding
MMA hypothesis
 Massive modularity
 Modern-day
phrenology?
Jerry Fodor: Modularity
 Differentiation of modules and central processing
systems
 Modules are:
 Domain-specific
 Rapid
 Informationally encapsulated
 Automatic – obligatory firing
 Shallow output
 Inaccessible to consciousness
 Characteristic pattern of breakdown - lesions
 „The moon looks bigger when it’s on the horizon; but I know
perfectly well it’s not. My visual perception module gets fooled,
but I don’t. The question is: who is this I?[…] If, in short, there is
a community of computers living in my head, there had also
better be somebody who is in charge; and, by God, it had better
be me. ” Jerry Fodor on Pinker and Plotkin
 Jerry Fodor: The trouble with psychologicalDarwinism. London
Review of Books
Reasoning circuits – rational
instincts
1. Structured around an adaptive problem
2. Universally present in homo sapiens
3. Develop without conscious effort (speech
vs writing)
4. Applied without conscious effort
5. Distinct from more general abilities
Stone age minds
 EEA - environment of evolutionary adaptedness
 „For this reason, evolutionary psychology is relentlessly pastoriented…”
 What is problematic about this argument?
 Proximal and distal explanations in psychology
 Universalism
 the universal, species-typical architecture
 reliably develops across the (ancestrally) normal range
 psychic unity of humankind – as opposed to marvellous
cultural diversity
 (Donald Brown – the universal human)
 Margaret Mead – coming of age in the Samoa – Derek Freeman
Donald Brown
The Universal People
The total list comprises about 150 items
 Abstraction (in speech and in
thought)
 Language!
 baby talk
 Antonyms
 Nouns
 numerals
 Belief in supernatural/religion –
magic (wicca)
 Beliefs about death, disease,
fortune & misfortune
 Binary cognitive distinctions –
antonyms
 Childhood fear of strangers/loud
noises
 Coalitions
 Collective identities
 Cooperation & competition
 Morals
 Murder prohibited
 Rape prohibited
 Myths & narratives













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Meals & meal times
Marriage
Daily routines
Melody
Metaphors
Music
 Repetition&variation
Dance
Crying (emotions?)
Personal names
Planning
Prode
Promise
Recognition of individuals by face
Rhythm
Rites of passage & rituals
Oedipus complex – defense
mechanisms
 self-image
The importance of universalism
 In theory, evolution could explain diversity
– supposing a varying environment would
entail varying organisms
 Why is universalism so highly emphasized
then?
 Sociobiology and social Darwinism
Edward O. Wilson
 1971. Insect societies
 1975: Sociobiology: The New Synthesis
 1978: On human nature
 In a Darwinian sense the organism does not live for
itself. Its primary function is not even to reproduce other
organisms; it reproduces genes, and it serves as their
temporary carrier... Samuel Butler's famous aphorism,
that the chicken is only an egg's way of making another
egg, has been modernized: The organism is only DNA's
way of making more DNA
Edward O. Wilson
 People are animals, their behavior has evolved
just like that of the animals, and our culture has
a biological component
 altruism : self-destructive behavior performed
for the benefit of others – what other
explanation than culture?
Edward O. Wilson
 Culture is the slave of biology – it can only
survive as long as it supports biological needs
 Gathering of resources (territorial fights)
 cooperation – helping relatives
 Securing the continuity of the population
 Resonates to Nazi „Sozialbiologie”, genetic
determinism, eugenics
Richard Lewontin
Not in Our Genes
 Population geneticist – locus studies
 The concept of niche and interaction – the environment
does not form passive creatures according to its own
accord
 Deterministic perspective is false : biological creatures
are actively forming their environment
 Sould it be different the homo sapiens would not be alive by
now
 Legitimation and ideology – first God and now science is the
weapon – universities the factories that produce them
The danger in evolutionary belief
 Sociobiology
 The mere idea of struggle and survival is inherent in
nature and it is inevitable gives moral justification
towards the „unfit”
 Mary Midgley: Evolution as a Religion
 „Facts will never appear to us as brute and
meaningless; they will always organize themselves
into some sort of story, some drama”
 Buss: the moral/naturalistic fallacy (Dawkins
examines it as well)
 Does studying heart attack cause heart attacks?
Eugenics
 Eu – good, well (euphoria)
 Genics – (genes) born
(genetics)
 any human action whose
goal is to improve the
gene pool
 Renaissance idea:
improvement of the world
through science: why not
better humankind?
Second International Eugenics
Conference, 1921
Popularity of eugenics
 Originally a field of science!
1859
1900
1920
1940
1950
1992
Multifaceted Eugenics
 Trait
 Intelligence
 Mental diseases
 Detrimental mental
traits - criminality
 Physical diseases
(tubercolosis)
 Race
 Means:
 Dissemination of
information and free
choice
 Vocational counselling
 Genetic counselling
 Marriage restriction
 Segregation
 Compulsory sterilization
 Compulsory abortion
 Forced pregnancy
 Genocide
Sir Francis Galton (1822-1911)
 Charles Darwin’s halfcousin
 and a child prodigy
 Statistician
 Correlation
 Medical studies
 1960 – Oxford Evolution
Debate
Hereditary Genius
 Count the number of the relatives of various degrees of
eminent men
 Proposed:
 adoption studies
 trans-racial adoption studies
 Twin studies
 adopted and non-adopted
 Later: dyzigotic and monozygotic
 Aware of the nature-nurture debate
 1883: invented the word eugenics (Inquiries into human
faculty and its development)
 Dysgenic behaviour of eminent people
 Introducing monetary incentives
The Galton Institute (Former Eugenics
Society)
The Bell Curve, 1994
 Intelligence predicts:
 Financial income
 Job performance
 Crime
 Intelligence is
inherited 40-80%
 Perils of a custodial
State
The Bell Curve, 1994
 Intelligence is normally
distributed - g
 sum of many small random
variations in genetic and
environmental factors
 Racial claims –
differences between
blacks and whites
 Controversial – APA
Intelligence: Knowns
and Unknowns
 At present, no one
knows what causes
this differential.
Validity problem
National Longitudinal Survey of Labor Market Experience of Youth
California, 1900-1940s
 Eugenics flourishing
 Influential group of intellects endorsed and
financed eugenic projects
 Haynes – physician in Los Angeles (bronchitis!)
 Goethe – businessmen of Sacramento
 Cold Spring Harbor Station – research facility
 Aggravated by the Great Depression
 „act of civilizing” & Manifest Destiny
 Sinophobia and discrimination, scientific racism
California, 1900-1940s
 Eugenics flourishing
 Active involvement of governmental
organizations
 Large-scale administration of IQ tests
 Authorization of scientific research and sterilization
 Expulsion of foreigners and undesirables en
masse
 Fomented racial segregation
 IQ testing – two-tracked school system
California, 1900-1940s Eugenics
 Victims:
 Racial groups
 Immigrants
 Mexicans
 Asian Americans
 African Americans
 Young girls classified as
 Immoral
 Delinquent
 3 stages : liberal – state – liberal
Liberal starting point
 1910 Terman’s Binet-Simon test
 Whites
 Mexicans
 Negroes
 Intelligence tied to Nordic blood…
 Segregation
 Vocational counselling
Sterilizations per annum 1909-1936
 Haynes in Los Angeles
sterilizations per annum
900
 Society organized for wellbeing
 Regulate and streaamline
800
700
600
500
 Gosney and Popenoe
400
300
 Sterilization for Human
Betterment
200
100
0
1909
1920
1929
1936
1942
1952
 Major themes:
 Delinquency
 Mental retardedness
 1935 HOGUE’s bill – to
extend sterilization did not
pass
 Competent decision
boards:
 Directors, wardens and
superintendents
 Drop in 1952
 Administrative measures
PROTECTION - NOT PENALTY
 emphasis shifts from heredity to capacity
and responsability of parenthood and
social skills
 Change in methods towards liberal measures
in 1940
 Popenoe
 Counselling – career planning, marriage, family planning
 Information dissemination on eugenical measures
 Holmes (1920) monetary incentives
The motives shifted
 Early years – genes deflate the germ plasm
(1880)
 Initially against: criminality, imbecility, poverty…
 White supremacy, racial segregation, stereotypes
 Mexican boys – mentally incompetent – forced manual
workers
 Mexican women – hyperbreeders dependent on
welfare
 Defectives depleting resources – fiscal
justifications
Herbert Spencer
 Social darwinism
 Taking „survival of the fittest” a step too far
 Darwin himself thought it impractical – he would
rather have spread the knowledge and let people
decide for themselves
 2 basic mistakes
 Naturalistic fallacy
 He conflates development with change
 Probably a side effect of the ancient idea of the scala naturae
Internal struggles
 Evolution by selection is the only known causal process
capable of creating such complex organic mechanisms.
(David Buss)
 Jerry Fodor
 The motiv is inaccessible even to the agent
 A way of restoring our innocence
 Psychological Darwinism is a kind of conspiracy
theory; that is, it explains behaviour by imputing an
interest (viz in the proliferation of the genome) that
the agent of the behaviour does not acknowledge.
 Popular for the same reason Freud was popular: a
slip of tongue is just a libidinous impulse
Objections : Jerry Fodor
 Is it ONLY adaptationism that is able to explain such
complexity?
 The complexity of behaviour itself is irrelevant
 evolution does not and can not act on it
 only on brains
 What matters is how much you would have to change an ape’s
brain in order to produce that much complexity in behaviour
 „ And about this, exactly nothing is known. ”
 It is not like the giraffe’s neck – longer is evident
 In fact the difference between brains is not that big (J.F.)
 in terms of genes it is even smaller

„what matters with regard to the question whether the mind is an adaptation is not
how complex our behaviour is, but how much change you would have to make in an
ape’s brain to produce the cognitive structure of a human mind. And about this,
exactly nothing is known. That’s because nothing is known about how the structure of
our minds depends on the structure of our brains.”
Objections : Jerry Fodor
 Methodological flaw: „reverse engineering”
 inferring how a device must work from a prior
appreciation of its function
 Ever tried using telnet?
 you don’t have to know how hands (or hearts, or eyes, or livers)
evolved to make a pretty shrewd guess about what they are for.
Maybe you also don’t have to know how the mind evolved to
make a pretty shrewd guess at what it’s for; for example, that it’s
to think with. (Fodor, J.)
Concerns with evolutionary
psychology
 Level of selection
 Individual
 Gene
 Group
 Question of fitness & adaptation
 Small designs that lead to a higher reproduction of a trait
 CIRCULARITY
 Fitness (reasoning circuits) has a definition
 Yet how do you recognize it in retrospect?
 Which one is the result of an adaptation?
 Xenophobia
 colour of bones
 form of earlobes
The circular argumentation
problem
 Inherent goal – often evokes attacks of circular
argumentation – the reverse engineering
problem
 The effects strive towards the goal
 The goal preexists (who invented the goal?)
 Answer – evolutionary forces
 How do you know this was the goal?
 Because it is reached!
Just-so stories (Rudyard Kipling)
Problems with blind adaptationism
1. The Panglossian Paradox
2. Graduality does not always work – saltational
models (one day you wake up speaking a
language?)

George Jackson Mivart - what do you do with 5% of
a wing?

Gould: exaptations
3. Physical constraints – Gould: spandrels
in the cathedral
The Panglossian Paradox
 Candide, ou l'Optimisme by Voltaire
 Critique of the Leibnizian mantra of Pangloss, "all is
for the best in the best of all possible worlds"
 "Tout est pour le mieux dans le meilleur des
mondes"
 theodicy of Gottfried Wilhelm Leibniz
 God is a benevolent deity –> the world is perfect
 Dr. Pangloss, professor of "métaphysico-théologocosmolonigologie" and self-proclaimed optimist
The Panglossian Paradox
 Lisbon's harbor episode, where honest James dies
 Candide, who beheld all that passed and saw his benefactor one
moment rising above water, and the next swallowed up by the
merciless waves, was preparing to jump after him, but was
prevented by the philosopher Pangloss, who demonstrated to
him that the roadstead of Lisbon had been made on purpose for
the Anabaptist to be drowned there.
 Pangloss on his own syphilis
 it was a thing unavoidable, a necessary ingredient in the best of
worlds; for if Columbus had not caught in an island in America
this disease, which contaminates the source of generation, and
frequently impedes propagation itself, and is evidently opposed
to the great end of nature, we should have had neither chocolate
nor cochineal.
 The best of all possible worlds
 It is demonstrable that things cannot be otherwise
than as they are; for as all things have been created
for some end, they must necessarily be created for
the best end. Observe, for instance, the nose is
formed for spectacles, therefore we wear spectacles.
 Have we replaced God by evolution? - Is the
world the best of all possible worlds?
 On the function of our noses:
 Is its inherent purpose
 to hold spectacles?
 to warm and moisturize air?
 How are you to tell in retrospect?
Exaptation, cooption, preadaptation
 NOT everything is an adaptation
 Human vestigiality has long been observed
 Tailbone
 Vermiform appendix
 Muscles in the ear
 Shifts in the function of a trait during evolution
 Cooption had a slight confusion with non-adaptive traits less used
 Darwin already outlined the basis in the „Origin of Species”
 bird feathers – originally thermo-regulatory function – adapted to flight
 Mivart: the paradox of 5% of a wing!
 Jury-rigged design – apparent non-functional traits might be telling
about the original function
Exaptation, cooption, preadaptation
 Recently – Stephen J. Gould: The thumb of the
Panda
 (uses the word exaptation)
 The tinkertoy approach
 Odd arrangements and funny solutions are the proof
of evolution--paths that a sensible God would never
tread but that a natural process, constrained by
history, follows perforce.
 Other examples:
 Mammals – lactatory glands
 Flat feet – squat eating – bipedalism
 Bones – calcium deposits primarily
Physical constraints
 Venice: St Mark’s Cathedral
Stephen J. Gould and
Richard Lewontin
"The Spandrels of
San Marco and
the Panglossian Para
digm: A Critique of the
Adaptationist
Programme" (1979)
Are the spandrels there, so that nice paintings could be
painted on them, specially designed for that purpose?
More likely to be inherent in the Bauplan –
constraint on adaptive evolution
Causes of historical origin must always be separated from current
utilities; their conflation has seriously hampered the evolutionary
analysis of form in the history of life.
Physical constraints
 Does the tyrannosaur’s
hands are especially
useful in titillating females
– is this a good
explanation for its
adaptive value?
 Blind adaptationism does
not differentiate between
original function and
current potentialities
 Just-so-stories
 Physical constraints – like
spandrels – do not need
an evolutionary
explanation
In the age of Reason
 What is the argument that Tooby and
Cosmides make about reasoning?
 Think of the WASON task!
 General problem solving
 Specialized problem-solving modules
 Mathematics – a basic concept or a high
art?
 An argument can be made for both
 How to make life difficult
Deduction and Induction
 If it rains I’ll take an umbrella with me
 It is raining.
 I take an umbrella with me.
 I take an umbrella with me
 It is either raining or not
 It is not raining
 I either take an umbrella with me or not
 I do not take an umbrella with me
 It is not raining
 John studied accountancy at university.
 John works at an accountant’s office.
 Therefore John is an accountant.
Modus ponens
Modus tollens
The Wason task – deduction task
 There are 4 cards on the table
E
K
2
7
 Each card has a letter on one side and a number on the
other
 RULE: If the card has a wovel on it, the other side
must have an even number on it
 Which one(s) do you have to turn to know if they
conform to the rule or not?
The
Wason
task
 There are 4 cards on the table
beer
Coke
22
17
 All cards have a drink on one side and the age
on the other
 RULE: If one drinks alcohol, they need to be
over age
 Which one(s) do you have to turn to know if they
conform to the rule or not?
 Why the difference?
 Social rules
 Evolutionary psychology – cheater detectors?
 What is the counter-argument to that?
Some provocative questions
 Does natural selection still work in our
highly artificial society?
 What will the homo sapiens be like in
another 200.000 years?
 Why are there mental illnesses, if
adaptationism is so powerful in
evolutionary psychology?