Reflective process

Introspection is the examination of one's own conscious thoughts and feelings. In psychology the process of introspection relies exclusively on observation of one's mental state, while in a spiritual context it may refer to the examination of one's soul. Introspection is closely related to human self-reflection and is contrasted with external observation.

Introspection generally provides a privileged access to our own mental states, not mediated by other sources of knowledge, so that individual experience of the mind is unique. Introspection can determine any number of mental states including: sensory, bodily, cognitive, emotional and so forth.

Introspection has been a subject of philosophical discussion for thousands of years. The philosopher Plato asked, "…why should we not calmly and patiently review our own thoughts, and thoroughly examine and see what these appearances in us really are?" While introspection is applicable to many facets of philosophical thought it is perhaps best known for its role in epistemology, in this context introspection is often compared with perception, reason, memory, and testimony as a source of knowledge.

It has often been claimed that Wilhelm Wundt, the father of modern psychology, was the first to adopt introspection to experimental psychology though the methodological idea had been presented long before, as by 18th century German philosopher-psychologists such as Alexander Gottlieb Baumgarten or Johann Nicolaus Tetens. Also, Wundt's views on introspection must be approached with great care. Wundt was influenced by notable physiologists, such as Gustav Fechner, who used a kind of controlled introspection as a means to study human sensory organs. Building upon the pre-existing use of introspection in physiology, Wundt imposed exacting control over the use of introspection in his experimental laboratory at the University of Leipzig making it possible for other scientists to replicate his experiments elsewhere, a development that proved essential to the development of psychology as a modern, peer-reviewed scientific discipline.

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