Early experimentalists

• Psychology is meant as an "intro to psychology" with three units: History, Developmental, Learning, and one test per unit
• Why study the history of Psychology?

  Reveals how concepts and approaches to mind have changed, and a history of wrong ideas – pseudoscience
• Key reasons to study the history of Psychology


  • Learn about key advances in study of mind
  • Evolving schools of thought and zeitgeists
  • Place contemporary psychology in context
• Psychology: psyche – mind/soul, & logia – to study
• H. Ebbinghaus (1850-1909): '"The history of psychology is short, but its past is long"'
• Psychology


  • Relatively 'young' science, less than 200 years old
  • However, study of human nature is much older
• Ancient Greek Thought


  • Before development of science, the world was viewed as full of minds (souls, spirits) and magic
  • Greek science was the first step towards 'naturalistic' view of the world
• There is sometimes a difference between appearance and reality
• Plato's Rationalism


  Senses can be deceiving, so people should rely on logic instead
• Allegory of the Cave


  • Prisoners in a cave can only see shadows on a wall, which become their reality
  • Only once they leave the cave can they see 'real' objects
• Empiricism


  Emphasises role of experience, gains information through sensory perception and observation
• Aristotle


  • Gained knowledge from observation, believed observation and analysis are reliable
  • Did no experimentation, but studied living things and analysed the nature of causes
  • Defined the 'soul' as that which animates and gives form to matter
• After the fall of the Roman empire, Greek ideas were preserved by Islamic scholars and later rediscovered by Christian scholars during the Scientific Revolution and Enlightenment
• Rene Descartes' Mind-Body Dualism


  • Made an ontological distinction between Mind (res cogitans) and Matter (res extensa), which are fundamentally different
  • The human mind is uniquely reflexive, linguistic and rational
• John Locke


  Themes: How do we acquire knowledge?, Nature vs. Nurture, We do not have innate ideas, Perception vs. Reality
• David Hume's Skepticism


  Argued that reason is the slave of passions, and that experience actually provides fewer grounds for belief than we conventionally assume
• Hume's problem of falsifiability: "No amount of observations of white swans can allow the inference that all swans are white, but the observation of a single black swan is sufficient to refute that conclusion"
• Hume argued that repeated instances do not justify ontological induction, and that correlation is not causation
• In the 19th century, empirical science started investigating the senses experimentally, and applying physiology to the study of the mind
• The case of Phineas Gage raised the question of whether "the Mind of Man" is no more than a mechanism
• Early experimental psychology


  • Quantifying psychological processes through psychometrics, psychophysics, and structuralism
• Early Experimentalists


  • Francis Galton
  • Alfred Binet
  • Franz Joseph Gall
  • EH Weber
  • Hermann von Helmholtz
  • Wilhelm Wundt
  • William James
• Psychometrics


  Science of measuring mental faculties like intelligence, personality, aptitudes, mental illness, and educational problems
• Sir Francis Galton


  • Cousin of Darwin, made contributions to statistics and the study of intelligence
  • Suggested intelligence could form a normal distribution, developed standard deviation and regression to the mean
• Galton's statistical contributions


  • Standard deviation
  • Regression to the mean
  • Pearson's Correlation Coefficient
• Galton's Hereditary Genius


  Individual differences in intelligence must be innate, and intelligence runs in families
• Galton's Inheritance of Eminence showed that the closer the kinship, the greater the likelihood of eminence
• Galton's Eugenics


  Improving the human race through selective breeding, based on the idea that humans can be bred like horses
• Eugenics was generally abandoned after the early 20th century
• Characteristics of Science vs. Pseudoscience


  • Science: Systematic Observation, Ruthless peer review, Considers all evidence, Invites Criticism, Repeatable results, Limited claims, Specific terms and operational definitions, Engages community, Changes with new evidence, Follows evidence where it leads
  • Pseudoscience: Anecdotal Evidence, No peer review, Considers only positive evidence, Dismisses criticism, Non-repeatable results, Grandiose claims, Vague terms and ideas, Isolated, Dogmatic and unyielding, Starts with a conclusion, works back to confirm
• Binet intelligence scales


  First usable test of intelligence, comprising 30 separate items of increasing difficulty, and considering age
• Intelligence Quotient (IQ)


  Introduced by William Stern in 1912, IQ = mental age / chronological age x 100, higher IQ = superior intellectual level
• Intelligence testing and IQ is still in common use today, with tests like the Wechsler Adult Intelligence Scale (WAIS) and Wechsler Intelligence Scale for Children (WISC)
• The problem of subjectivity in measuring the mind led to a focus on studying objective things like perception, sensation, and physical components
• Franz Joseph Gall


  • Found nerve fibres passing from one side to the other of the brain (commissures)
  • Comparative anatomist who compared brains, and believed the larger the brain the more advanced
• Intelligence Quotient (IQ)


  Measure of intelligence introduced by German psychologist William Stern in 1912
• Calculating IQ


  Mental age / Chronological age x 100
• Higher IQ


  Indicates superior intellectual level
• Intelligence testing today


  • Mental testing and IQ is still in common use, but much developed
  • Tests often updated every few years
  • Wechsler Adult Intelligence Scale (WAIS) and Wechsler Intelligence Scale for Children (WISC) are commonly used
• Galton's and Binet's ideas very influential and have had a major impact on modern psychology