In this work my aim is to present the anthropological aspects of the same subject treated of in my psychological investigation of animal play, published in 1896, which may be said to have been a pioneer attempt in its department. In the discussion of human play, however, I am supported by valuable philosophical works, among which I acknowledge myself especially indebted to those of Schaller, Lazarus, and Colozza. In regard to the standpoint from which I approach the general problem of play, it is hardly necessary for me to speak at length here. It is the same practice theory on which I intrenched myself in the earlier work. The difficulties in its way, arising from our as yet imperfect understanding of human impulse life, are fully allowed for in the introduction to the first section, and I am convinced that the results attained by its adoption will, on the whole, justify the method of treatment which I have chosen. Since it was my interest in æsthetics which first induced me to turn my attention to the subject of play, it is natural that the æsthetic phase of the question should be conspicuous in this volume. Still, I wish it to be distinctly understood that my inquiry has not been conducted solely in obedience to such leadings, nor should it be judged exclusively by æsthetic criteria. I have intentionally left many questions open for more mature consideration, at some future time, when I can give to them more thought than was possible in the year’s study which I have devoted to play phenomena. KARL GROOS. BASEL, _December, 1898_. CONTENTS PAGE EDITOR’S PREFACE iii AUTHOR’S PREFACE v THE SYSTEM OF PLAY—INTRODUCTION 1 PART I _PLAYFUL EXPERIMENTATION_ I. PLAYFUL ACTIVITY OF THE SENSORY APPARATUS 7 1. Sensations of contact 7 2. Sensations of temperature 14 3. Sensations of taste 14 4. Sensations of smell 16 5. Sensations of hearing 18 (_a_) Receptive sound-play 19 (_b_) Productive sound-play 31 6. Sensations of sight 48 (_a_) Sensations of brightness 50 (_b_) The perception of colour 54 (_c_) Perception of form 60 (_d_) Perception of movement 67 II. PLAYFUL USE OF THE MOTOR APPARATUS 74 A. Playful movement of the bodily organs 75 B. Playful movement of foreign bodies 95 1. Hustling things about 95