The Sepher Yetzirah although this name means The Book of Formation is not in any sense a narrative of Creation or a substitute Genesis but is an ancient and instructive philosophical treatise upon one aspect of the origin of the universe and mankind an aspect at once archaic and essentially Hebrew. The grouping of the processes of origin into an arrangement at once alphabetic and numeral is one only to be found in Semitic authors. Attention must be called to the essential peculiarity of the Hebrew language the inextricable and necessary association of numbers and letters every letter suggesting a number and every group of letters having a numerical signification as vital as its literal meaning. The Kabalistic principles involved in the reversal of Hebrew letters and their substitution by others on definite schemes should also be studied and borne in mind. It is exactly on these principles that the groundwork idea of this disquisition rests and these principles may be traced throughout the Kabalistic tractates which have succeeded it in point of time and development many of which are associated together in one volume known as the Zohar which is in the main concerned with the essential dignities of the Godhead with the Emanations which have sprung therefrom with the doctrine of the Sephiroth the ideals of Macroprosopus and Microprosopus and the doctrine of Reincarnation. The Sepher Yetzirah on the other hand is mainly concerned with our universe and with the Microcosm. The opinions of Hebrew Kabalistic Rabbis and of modern mystics may be fitly introduced here. The following interesting quotation is from Rabbi Moses Botarel who wrote his famous Commentary in 1409It was Abraham our Fatherblessed be hewho wrote this book to condemn the doctrine of the sages of his time who were incredulous of the supreme dogma of the Unity. At least this was the opinion of Rabbi Saadiahblessed be heas written in the first chapter of his book The Philosophers Stone. These are his words T