Who Are the Key Figures in the History of Psychology?

Psychology During the Ancient Times: Philosophy and Physiology

The scope of psychology involves the study of behaviors and mental processes. These two topics have been studied during the ancient times by philosophers and physiologists, alike. In Philosophy, Socrates, Plato, and Aristotle speculated about consciousness, rationality, and free will. In Physiology, Hippocrates, known as the "father of medicine," observed how the brain controls various organs of the body. His observations influenced the development of the biological perspective in psychology.

17th-Century Psychology: The Nature-Nurture Debate

A psychological debate that continues even today is about the source of behaviors and mental processes, that is, whether they are products of the external environment, or they spring forth from our inborn capabilities. This debate actually started during the 17th century, when René Descartes and John Locke argued about the source of knowledge. The nature view holds that knowledge is inborn or innate, while the nurture view holds that knowledge is acquired through experiences.

In an argument for the nature view, René Descartes contends that the innateness of ideas, such as God, the self, geometric axioms, perfection, and infinity, reflects the innateness of knowledge. He also thought of the body as a machine, the structures and functions of which are inborn. His idea that the body is like a machine that can be rendered for study is a precursor to the information-processing perspective in psychology.

In an argument for the nurture view, John Locke, an English philosopher, contends that the human mind is a blank slate, or a tabula rasa, written by experiences. His idea influenced the development of associationist psychology.

Although the nature-nurture debate continues today, most psychologists attempt to integrate the views, preferring to understand their interaction, instead.

19th-Century Psychology: Beginnings of Scientific Psychology

While the first two periods is when psychologists trace the roots of its scope, the 19th century is when psychology is finally established as a scientific study.

Wilhelm Wundt established the first psychology laboratory at the University of Leipzig in Germany in 1879. He studied mental processes via Introspection, or the observation and recording of personal perceptions, thoughts, and feelings, in response to visual stimuli. Introspection later proved to be unworkable and inconclusive because too much individual variations in reporting posed difficulty in data interpretation.

Inspired by the advances in chemistry and physics, E. B. Titchener, a Cornell University psychologist trained by Wundt, developed Structuralism, or the analysis of mental structures. For example, he identified the elements of taste into sweet, salty, sour, and bitter.

Inspired from the publication of Charles Darwin's Theory of Evolution by Natural Selection, William James, a distinguished psychologist at Harvard University, developed Functionalism, or the analysis of how the mind helps organisms adapt and function in their environment. It is the precursor for evolutionary psychology.

Introspection, structuralism, and functionalism were eventually let go because they significantly limit psychological research to conscious experiences only.

Early 20th-Century Psychology: The Schools of Psychology

During the early 20th century, 3 schools of thought in psychology emerged: Behaviorism, Gestalt Psychology, and Psychonalysis.

John B. Watson shifted the focus of psychology from private conscious experiences to public overt behaviors. Building upon the research of Russian physiologist Ivan Pavlov on classical conditioning, Watson developed Behaviorism, a new school of psychology which proposes that behavior is a result of conditioning or shaping of the environment through reinforcements (rewards) or punishments. According to behaviorism, the Conditioned Response is the smallest unit of behavior. It interlinks with other conditioned responses to form complex behavior patterns. Stimulus-Response (S-R) Psychology is the language of behaviorism. Behaviorists analyze behavior in terms of stimuli and responses.

Max Wertheimer, Kurt Koffka, and Wolfgang Köhler are German psychologists who emigrated to the United States. Together, they developed Gestalt Psychology, a new school of psychology which defines perceptual experiences as the relationship among the parts of the stimuli. "Gestalt" is a German word which means "form" or "configuration." Gestalt psychology developed principles that characterized as automatic and not conscious. Its famous dictum: "The whole is greater than the sum of its parts." Its research served as the precursor to the development of cognitive psychology. Application of gestalt principles to interpersonal phenomena lead to the development of social psychology.

Sigmund Freud developed Psychoanalysis, a new school of psychology that is both a theory and a method of psychotherapy, which attempts to understand the nature and expression of the unconscious. The unconscious is an entity of the mind that houses early childhood's forbidden sexual and aggressive impulses, which are driven out of conscious awareness, but continue to influence thoughts, feelings, and behaviors. It manifests itself in dreams, slips of the tongue, and mannerisms. One technique in psychoanalysis is Free Association, the method of allowing a person to speak freely in order to bring out the unconscious into awareness.

Behaviorism was the most popular among the 3 schools of psychology, until World War II, when sophisticated instruments and electronic equipment gave rise to other factors that complicate the scope of psychology.

Late 20th-Century Psychology: Sophisticated Technological Advances

Herbert Simon, a Nobel prize winner, was inspired by computers and how they work. He developed information-processing models that view human beings as processors of information. He analyzed and likened memory to how computers transfer data from RAM to hard drive.

Noam Chomsky introduced psycholinguistics in his book Syntactic Structures (1957). Psycholinguistics is the study of mental processes involved in language comprehension and speech.

Also a Nobel prize winner, Roger Sperry utilized technological advancements in biomedicine to develop neuropsychology, the study of the relationship of specific brain regions and particular thoughts and behaviors.