Group Psychology and the Analysis of the Ego (German: Massenpsychologie
und Ich-Analyse ) is a 1921 book by Sigmund Freud, the founder of
psychoanalysis.
In this monograph, Freud describes psychological mechanisms at work within
mass movements. A mass , according to Freud, is a "temporary entity,
consisting of heterogeneous elements that have joined together for a moment."
He refers heavily to the writings of sociologist and psychologist Gustave Le
Bon (1841-1931), summarizing his work at the beginning of the book in the
chapter Le Bons Schilderung der Massenseele ("Le Bon's description of the
group mind").