animals, made of wood and stone and various materials; and some
of the prisoners, as you would expect, are talking, and some of
them are silent?

This is a strange image, he said, and they are strange prisoners.

Like ourselves, I replied; and they see only their own shadows,
or the shadows of one another, which the fire throws on the
opposite wall of the cave?

True, he said: how could they see anything but the shadows if
they were never allowed to move their heads?

And of the objects which are being carried in like manner they
would see only the shadows?

Yes, he said.

And if they were able to talk with one another, would they not
suppose that they were naming what was actually before them?"_
--The Republic of Plato, Book Seven. (Jowett Translation.)


CONTENTS

PART I. INTRODUCTION

I. The World Outside and the Pictures in Our Heads

PART II. APPROACHES TO THE WORLD OUTSIDE