Evolution of Psychology

Modern psychology, shaped heavily by Western intellectual history, has a comparatively short formal life even though it grew out of a much older tradition of philosophical inquiry into questions of real psychological significance. Its formal starting point is usually placed at 1879, when Wilhelm Wundt set up the first experimental psychology laboratory in Leipzig, Germany. Wundt wanted to analyse the basic building blocks of conscious experience, and the method his followers used for this was introspection -- asking trained subjects to describe their own mental processes and experiences in careful detail. Because these introspective reports could not be checked or verified by an outside observer, many psychologists eventually judged introspection too subjective to count as properly scientific, and this dissatisfaction opened the door to several competing new perspectives.

One of the earliest reactions came from the American psychologist William James, who set up his own laboratory at Cambridge, Massachusetts, shortly after Leipzig, and developed the functionalist approach: instead of asking what the mind is structurally made of, functionalists asked what the mind does -- specifically, how mental processes and behaviour help a person adapt to and deal with their environment, satisfying their needs. James treated consciousness as an ongoing stream of mental activity in constant interaction with the environment, and the educational thinker John Dewey used functionalist ideas to argue that people function effectively precisely by adapting to their surroundings.

In the early twentieth century, Gestalt psychology emerged in Germany as a direct reaction against Wundt's structuralism. Rather than breaking perception down into separate components, Gestalt psychologists argued that a person's actual perceptual experience is always more than the sum of the individual inputs feeding into it -- light from a rapid sequence of separate flashing bulbs is perceived as continuous movement, and a movie, which is really a fast-moving sequence of still photographs, is perceived as one smooth, ongoing scene. Around the same period, behaviourism offered a second, quite different reaction to structuralism. Around 1910, John Watson, strongly influenced by Ivan Pavlov's work on classical conditioning, rejected mind and consciousness altogether as legitimate subject matter for psychology, arguing that only what is observable and independently verifiable -- behaviour, understood as measurable responses to stimuli -- belongs in a scientific psychology. B.F. Skinner later extended and popularised behaviourism across a very wide range of situations, and behaviourists dominated psychology for several decades after Watson. …