one hears the details. Scientists and scholars of the highest eminence
were drawn into the conflict, which has not yet wholly subsided,
although the present report must be regarded as quite final in its
verdict.

As for Hans himself, he has become the prototype of a host of less
distinguished imitators representing every level of animal life, and
when last heard from he was still entertaining mystified audiences by
his accomplishments.

But the permanent worth of the book is not to be found in its record of
popular excitement, interesting as that is. It is a document of the very
first consequence in its revelation of the workings of the animal mind
as disclosed in the horse. Animal lovers of all kinds, whether
scientists or laymen, will find in it material of greatest value for the
correct apprehension of animal behavior. Moreover, it affords an
illuminating insight into the technique of experimental psychology in
its study both of human and animal consciousness. Finally, it contains a
number of highly suggestive observations bearing on certain aspects of
telepathy and muscle-reading. All things considered, it may fairly be
said that few scientific books appeal to so various a range of interests
in so vital a way.

Readers who wish to inform themselves of all the personal circumstances
in the case may best read the text just as it stands. Those who desire
to get at the pith of the matter without reference to its historical
settings, may be advised to omit the Introduction by Professor Stumpf of
the University of Berlin, together with supplements II, III and IV.

CONTENTS

PAGE
PREFATORY NOTE (By JAMES R. ANGELL) v

INTRODUCTION (By C. STUMPF) 1

CHAPTER
I. THE PROBLEM OF ANIMAL CONSCIOUSNESS AND "CLEVER HANS" 15

II. EXPERIMENTS AND OBSERVATIONS 30

III. THE AUTHOR'S INTROSPECTIONS 88

IV. LABORATORY TESTS 102

V. EXPLANATION OF THE OBSERVATIONS 141

VI. GENESIS OF THE REACTION OF THE HORSE 212

CONCLUSION 240

SUPPLEMENTS:

I. MR. VON OSTEN'S METHOD OF INSTRUCTION (By C. STUMPF) 245

II. THE REPORT OF SEPTEMBER 12th, 1904 253

III. AN ABSTRACT FROM THE