Individual Differences are Obvious
•	Most obvious
–	Class
–	Gender
–	Race
–	Age
–	Personality
–	Intelligence
•	Genetic or environmental?
Late Victorian Obsession with Individual Differences
•	Rise in interest through 19th Century for English
•	Social Darwinism and eugenics
•	How to incorporate race and gender
•	Theory of evolution
–	Provides for intermediate “forms” or species
–	“Humanness” has to be defined
The Science of Individual Differences: Galton
•	Francis Galton (1822-1911)
•	Collected huge amounts of data
•	Fingerprints
•	Correlation coefficient
•	Hereditary Genius (1869)
•	Eugenics 
American H.H. Goddard
•	Ran home for feeble-minded boys and girls
•	Write extensively on hereditary retardation
•	Coined phrase “moron”
•	Supported modified eugenics
–	Institutionalization of retarded
–	Not necessarily sterilization
•	Most famous book on the Kallikak families
The Kallikaks (1913)
•	Martin Kallikak joined Revolutionary Army at age 17
•	Son by feeble-minded bar maid
•	Later married into a respectable family
Martin Kallikak’s “Bad” Family
•	480 descendants
•	143 feeble-minded
•	36 illegitimate
•	33 sexual immoral
•	24 alcoholics
•	3 criminal 
Martin Kallikak’s “Good” Family
•	496 descendants
•	All normal
•	Only 1 sexually loose man
•	Married into best families
•	Half dozen towns in New Jersey named after descendants
IQ Testing
•	Cattell
–	Theory based (Wundt)
–	Not valid
•	First test by Binet (1908)
–	Practical reasons
–	Did not assume differences were genetic
•	Stanford-Binet
–	Terman
–	Assumed heredity for racial and class differences
Yerkes and Army Alpha
•	Tests during WWI by Yerkes
•	Found that average mental age was 13
•	Much less among recent immigrants and minorities
–	Test highly sensitive to education
–	Yet assumed genetic
•	Partially responsible for restrictions on immigration during 1920s.
18th/19th Century Conceptions of Race
•	Race as common lineage
•	Race as discrete categories
Africans as Children – recapitulation
•	Haekel – ontogeny recapitulated phylogeny
•	So “less developed” races are like children
–	Physically – smaller brains
–	Emotionally
–	Intellectually
•	And seen as closer to apes or other primates
“Proof” of Genetic Group Differences
•	Finding empirical support
•	Most common was measuring brain size
–	Whites from Northern Europe always biggest
–	Jews and Asian somewhat less
–	Blacks lowest of all
–	Women smaller than men
•	Problems
–	Data selectively presented
–	No correction for stature or gender
The Criminal Face
•	Cesare Lombroso
•	Again the recapitulation argument
–	So criminality not merely genetic
–	But based on evolutionary program
•	Criminals more “ape-like”