Most modern psychology developed along the lines of Locke's view that the source of human knowledge
was through experience. Locke believed that all information about the physical world comes through
the senses and that all correct ideas can be traced to the sensory information on which they are based.
However, some European psychologists, remained loyal to Descartes' ideas that some mental organisation
is innate and this concept still plays a role in theories of perception and cognition.
Complimentary to this
philosophical background, psychology also received contributions from physiology. German physiologist
Johannes Müller tried to relate sensory experience both to events in the nervous system and to events in
the organism's physical environment. The first psychologists, Fechner and Wundt, introduced experimental
methods for measuring sensations in terms of physical magnitude of the stimuli producing them, and
in 1879 Wundt founded the first laboratory of experimental psychology. So, it was from this scientific
climate that Freud developed his theories of psychoanalysis and dream interpretation, calling attention to
the instinctual drives and unconscious motivational processes that determine people's behaviour.