Precursors to Scientific Psychology

Eighteenth and Nineteenth Century Precursors to Scientific Psychology

• Individualization: A societal trend toward looser social structures, prioritizing individual self-over group belonging; emerged around the late Middle Ages in Western societies.
• Contributing Factors to Individualization: Growing urbanization and industrialization fostered complex social networks and competition; diverse occupations and social relationships increased. Increased state control and information gathering created a sense of individuality. Religious emphasis on personal faith and connection with God encouraged individual focus. Mirrors and book printing heightened self-awareness and interest in others. Improved literacy and postal service enabled intimate personal communication.

British Empiricists

• Locke: Founder of empiricism; proposed the "tabula rasa" (blank slate) concept, influencing the idea of natural rights by emphasizing the inherent equality of individuals.
• Berkeley: Developed Idealism, suggesting that human knowledge is a mind-dependent construction, not necessarily reflecting an external reality. Mental phenomena are primary.
• Hume: Believed ideas originate from God, arguing that divine concepts are beyond reasoning and rely on perception. Questioned the reliability of scientific observation. "Esse est percipi" – existence depends on perception; introduced the problem of induction, questioning predictions based on past observations. Challenged causality, attributing it to mental habit rather than direct perception. Idealist.

Kant

• Transcendental Idealism: Aimed to reconcile empiricism with rationalism. Perception is more complex than Hume and Berkeley proposed; perception exists within a world in harmony with it.
• Noumena/Dinge an sich: Reality independent of perception—a stable external reality needed for understanding world order.
• Phenomena: Manifestations of things as they appear to us, shaped by perception and mental processes. Knowledge is limited to phenomena.
• Categories of Understanding: A priori lenses (e.g., time, space, cause/effect) through which we organize and interpret sensory data.

Reid

• Common Sense Realism: Perception directly represents external objects as they are, without intermediary perceptual representations.
• Division of Sciences: Distinguished between "proper science" (axioms & demonstrations like math) and "improper science" (historical/systematic arts).
• Physiognomy: Personality deduced from appearance, specifically facial features. Believed behavior needs to be considered in personality judgments.

Wolff

• Rational Psychology: Studied the mind using reason and metaphysical principles (e.g., immortality of the soul).
• Empirical Psychology: Studied the mind through observation and sensory experience. Supported introspection. Psychology should aim for mathematical demonstrations.

Comte

• Positivism: Criticized psychology for its lack of positivist scientific rigor. Claimed the proper study of the mind requires a biological and observational approach.
• Hierarchy of Sciences: Organized sciences based on complexity, beginning with mathematics and progressing to sociology.

Herbart

• Educational Philosophy: Importance of scientific approaches in education.
• Mathematical Models: Developed mathematical models to explain psychological phenomena, challenging Kant's view against a psychological science.

Bain

• Physiological Contributions: Incorporated the nervous system and physiology in psychology textbooks.

Psychological Experimentation

• Early Psychology Experiments: Natural philosophers conducted experiments categorized today as psychological studies. Emergence of early psychology laboratories.
• Human Perceptual Capabilities: Hooke examined minimum visual angles; Mayer studied illumination and detail perception; Weber studied just noticeable differences.
• Psychophysics: Studied stimulus-perception relationships (Fechner).

Mental Chronometry

• Measurement of Nerve Transmission: Von Helmholtz measured transmission speed in animals and humans.
• Scientific Study of Mental Processes: Donders initiated studies on the time course of mental processes.

Evolutionary Theory

• Evolutionary Context: Linnaeus's classification of humans with primates; fossil discoveries; increased plant cultivation. Cross-fertilization produced more adaptive offspring. Natural selection is the process by which the environment favors more advantageous traits.
• Natural Selection Critique: Jenkin criticized Darwin's theory, arguing that advantageous traits would weaken over time. Concepts of survival of the fittest.

Development of Statistics

• Individual Variation: Psychology differed from physics due to individual variation in response. Quetelet emphasized the predictive power of aggregating data.
• Statistical Methods: Fisher's Latin squares allowed better control for experimental factors.

Advancement of Medicine

• Patient-as-a-person Movement: Emphasized holistic patient care, treating patients as individuals rather than symptoms.

Reductionism

• Reductionism: The view that theories of mental properties can be reduced to neuroscientific theories; focuses on breaking down phenomena into simpler elements.