8                                    PREFACE.

Greek philosophers, although aiming at truth in the
abstract, never in all questions of popular bearing rise
much above the customary exoteric expressions and
tenets both of their religion and law. Besides Greek
ideas we shall only now and then mention those of the
Sufis or of some one or other Christian sect, because in
their notions regarding the transmigration of souls and
the pantheistic doctrine of the unity of God with crea¬
tion there is much in common between these systems.
I have already translated two books into Arabic, one
about the origines and a description of all created
beings, called Sdmkhya, and another about the emanci¬
pation of the soul from the fetters of the body, called
Patanjcdi (Pataiijala .?). These two books contain most
of the elements of the belief of the Hindus, but not
all the single rules derived therefrom. I hope that the
present book will enable the reader to dispense with
these two earlier ones, and with other books of the same
kind ; that it will give a sufficient representation of the
subject, and will enable him to make himself thoroughly
acquainted with it—God willing !