CLEVER HANS

(THE HORSE OF MR. VON OSTEN)

A CONTRIBUTION TO EXPERIMENTAL ANIMAL AND HUMAN PSYCHOLOGY

BY OSKAR PFUNGST

WITH AN INTRODUCTION BY PROF. C. STUMPF, AND ONE ILLUSTRATION AND FIFTEEN FIGURES

TRANSLATED FROM THE GERMAN BY CARL L. RAHN Fellow in Psychology in the University of Chicago

WITH A PREFATORY NOTE BY JAMES R. ANGELL Professor of Psychology in the University of Chicago

NEW YORK HENRY HOLT AND COMPANY 1911

Copyright, 1911 BY HENRY HOLT AND COMPANY