Alfred Russel Wallace, the origin of man, and spiritualism

The human brain processes information for decision-making using one of two routes: an intuitive system and a rational system (Epstein, 1994; popularized by Kahneman, 2011 as System 1 and System 2, respectively). The intuitive system is quick, impulsive, and operates with minimal effort, relying on emotions or habits to provide cues for what to do next, while the rational system is logical, analytical, deliberate, and methodical. Research in neuropsychology suggests that the brain can only use...

Structuralism, an early psychological theory developed by Wilhelm Wundt and his student Edward Bradford Titchener, sought to dissect the human mind into its most fundamental components. Wundt's groundbreaking work in his laboratory set the stage for Titchener to define structuralism's goal as cataloging the "atoms" of the mind—sensations, images, and feelings—akin to how chemists identify elements of matter.
Titchener's approach to structuralism was unique. He employed introspection, a method...

William James, John Dewey, and Charles Sanders Peirce were instrumental in founding functional psychology, which draws heavily from Darwin's theory of evolution by natural selection. This theory suggests that individual traits, including behaviors, are adapted to their environments through natural selection. At the heart of functionalism is the concept of adaptation, meaning that a trait enhances an individual's chances of survival and reproduction.
James envisioned psychology's role as...

Instinct theory proposes that innate biological instincts, like animal behavioral patterns, primarily drive human behavior. These instincts are inborn, not learned, and are fundamental to decision-making and action. Just as animals rely on instincts for critical survival functions such as migration, nest building, and defense, humans are also believed to exhibit behaviors rooted in evolutionary needs. For example, the instinct to reproduce motivates sexual behavior, while territorial instincts...

Carl Rogers, a key figure in humanistic psychology, believed that individuals possess an innate potential for growth and fulfillment. According to his model of personality, three significant components define an individual: the organism, the self, and conditions of worth.
The organism refers to an individual's inherent blueprint, which Rogers saw as innately positive and directed toward helping others, unlike Freud's view of the id as driven by base impulses. The self is a person's...

Gordon Allport, often regarded as the father of American personality psychology, developed a theory that emphasized the importance of understanding people in their present lives rather than focusing on their past, as psychoanalysis did. Allport believed that personality should be studied in healthy, well-adjusted individuals rather than those with psychological problems. He was particularly interested in defining traits, which he saw as fundamental mental structures that guide behavior across...