There is no doubt that the tetrad (τετρακτύς) of Pythagoras is an imitation of the Hebrew Tetragrammaton, and that the worship of the decade has simply been invented in honour of the ten Sephiroth. The four letters composing this name represent the four fundamental constituents of the body (i.e., heat, cold, dryness and humidity), the four geometrical principal points (i.e., the point, the line, flat and body), the four notes of the musical scale, the four rivers in the earthly paradise, the four symbolical figures in the vision of Ezekiel, &c., &c., &c. Moreover if we look at these four letters separately we shall find that each of them has equally a recondite meaning. The first letter ‏י‎, which also stands for the number ten, and which by its form reminds us of the mathematical point, teaches us that God is the beginning and end of all things. The number five, expressed by ‏ה‎ the second letter, shows us the union of God with nature—of God inasmuch as he is depicted by the number three, i.e., the Trinity; and of visible nature, inasmuch as it is represented by Plato and Pythagoras under the dual. The number six, expressed by ‏ו‎, the third letter, which is likewise revered in the Pythagorean school, is formed by the combination of one, two, and three, the symbol of all perfection. Moreover the number six is the symbol of the cube, the bodies (solida), or the world. Hence it is evident that the world has in it the imprint of divine perfection. The fourth and last letter of this divine name (‏ה‎) is like the second, represents the number five, and here symbolizes the human and rational soul, which is the medium between heaven and earth, just as five is the centre of the decade, the symbolic expression of the totality of things.