The principles of therapy are not altogether new. Each generation not only creates the new but deepens and en­ riches the meaning of the old. Theories and interpretations may change but there is a core of continuity to human ex­ perience that remains the same. Therapy as a technical devel­ opment belongs to our present century but the understand­ ing of the implications of therapy, conceived as it is in this book as a growth experience, is not alone of this generation. Plato’s Republic written twenty-three hundred years ago developed, in the allegory of the cave, an understanding of human psychological growth which seems to me to throw light on the therapeutic process of the present day.2