The Principles pf Psychology by William James was published in 1890. The text was based mainly on the observations
by James at the psychological laboratory he established in Harvard, 1876. This laboratory is the first of its kind in the USA at that time. There, William James developed his functional approach to psychology.
The findings of James indicates that although the mind operates as a part of the body, the mental faculties and adjustments of an individual are in fact environmental responses. In this book, Principles of Psychology , he defines the mind as an instrument in which, by controlling the will, choice, and effort, makes adjustments which are modified by factors that can be determined, such as heredity and biology. The book is notable for coining the term "stream of consciousness."
William James and the classic author Henry James are brothers.