<P> In 1890 , William James defined psychology as `` the science of mental life , both of its phenomena and their conditions '' . This definition enjoyed widespread currency for decades . However , this meaning was contested , notably by radical behaviorists such as John B. Watson , who in his 1913 manifesto defined the discipline of psychology as the acquisition of information useful to the control of behavior . Also since James defined it , the term more strongly connotes techniques of scientific experimentation . Folk psychology refers to the understanding of ordinary people , as contrasted with that of psychology professionals . </P>
<P> In 1890 , William James defined psychology as `` the science of mental life , both of its phenomena and their conditions '' . This definition enjoyed widespread currency for decades . However , this meaning was contested , notably by radical behaviorists such as John B. Watson , who in his 1913 manifesto defined the discipline of psychology as the acquisition of information useful to the control of behavior . Also since James defined it , the term more strongly connotes techniques of scientific experimentation . Folk psychology refers to the understanding of ordinary people , as contrasted with that of psychology professionals . </P>
who said psychology is the science of mental life
who said psychology is the science of mental life
William James
William James