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The Standard Social Science Model (SSSM)
(The “received wisdom” that EP is challenging)
1. The human mind is a blank slate (tabula
rasa).
2. Biological constraints on human behavior
are minimal.
3. Human behavior is shaped by (one or a
very few) general-purpose learning
mechanisms.
Critique of the SSSM
1. A blank slate could not respond to
experience because it would have no rules
for responding.
2. The nature/nurture (genes/environment,
innate/learned) dichotomy is false with
respect to ontogeny (development).
3. General-purpose learning mechanisms
cannot explain behavior.
4. SSSM separates natural and social sciences.
5. SSSM Lacks an overarching theory of
design.
Role of Culture
If culture an independent variable or a
dependent one?
In the SSSM view it’s wholly independent.
culture
human behavior
But where does culture come from?
Why don’t other animals have culture?
Why is human culture so constrained?
Why are there so many universals?
Role of Culture (cont.)
In the EP view its both dependent and
independent.
human nature
culture
human
behavior
Conclusions
The human mind is not an amorphous
computer.
It is content-rich (e.g., language-learning
abilities, intuitive physics, folk psychology).
It has many domain-specific cognitive and
emotional modules designed to meet
challenges that faced members of our
species over human evolution.
Evolution by Natural Selection
Differential perpetuation of alternative
replicating entities.
A
A
A
B
A
B
B
Copying fidelity must be high in comparison
to reproductive differential.
What are the replicating entities?
Individuals do not replicate faithfully enough.
Genes do.
Over development genes interact with the
environment to build phenotypes.
Phenotypes are more or less successful (in
part because of the genes that built them).
So genes that build more successful
phenotypes are differentially passed on to the
next generation.
Prerequisites for evolution by natural selection
1. heritable variation
2. that affects its own rate of replication
If this is true, then the variants that get
replicated at a higher rate will spread
through the population.
No moral imperative, it just will happen
whenever the prerequisites are met.
What does evolution by natural selection build?
It favors replicators (genes) that build
phenotypes that are good at transmitting
those replicators to future generations…
So, it builds “designs for reproduction”.
We call these adaptations.
Adaptation: A trait that exists because it
contributed to reproduction in ancestral
populations.
Adaptations
Are:
built of existing variation (mutations).
often formed slowly
often formed cumulatively
specialized
costly
and:
may be out of date
The Environment of Evolutionary Adaptedness
(EEA)