Ptolemy's Tetrabiblos: Book the First: Chapter XVI. Mutual Configurations of the Signs

CHAPTER XVI

MUTUAL CONFIGURATIONS OF THE SIGNS

THERE are certain familiarities or connections between different parts of the zodiac; and the chief of these is that which exists between such parts as are configurated with each other.

This mutual configuration attaches to all parts diametrically distant from each other, containing between them two right angles, or six signs, or a hundred and eighty degrees: it also exists in all parts at the triangular distance from each other, containing between them one right angle and a third, or four signs, or a hundred and twenty degrees; also, in all parts at the quadrate distance from each other, containing between them exactly one right angle, or three signs, or ninety degrees; and, also, in all parts at the hexagonal distance from each other, containing between them two-thirds of a right angle, or two signs, or sixty

1 These several distances are taken for the following reasons: the distance by diameter, however, is in itself sufficiently clear, and requires no further explanation; but, as to the rest, after the diametrical points have been connected by a straight line, AB; the space of the two right angles, contained on the diameter, is then to be divided into aliquot parts of the two greatest denominations; that is to say, into halves, AFC, CFB, and into thirds, AFD, DFE, EFB: there will then be provided for the third part (AD) a super-proportion (DC), equal to its own half; and for the half (AC) a super-proportion (CE), equal to its own third part; so that the division into two aliquot parts,

1.

---

Footnotes

25:1 Whalley, in his note upon this chapter, seems to have been surprised that no mention is made here by Ptolemy of the conjunction; but he overlooked the fact that the chapter treats only of parts of the zodiac configurated with each other; and that it was not possible for Ptolemy to conceive how any part could be configurated with itself. It is, therefore, by no means wonderful that the conjunction is not inserted here along with the rest of the aspects; although it is frequently adverted to in subsequent chapters, and its efficacy particularly described.

26:1 From the tenor of this chapter it was formerly doubted whether the author intended to admit in his theory only zodiacal aspects, and to reject those which are called mundane; but Placidus has referred to the 4th Chapter of the 8th Book of the Almagest (which will be found in the Appendix to this translation) to prove that Ptolemy distinctly taught two kinds of aspect; one in the zodiac and one in the world. Whalley quotes the opinion of Placidus, which he says is farther confirmed by the Lath Chapter of the 3rd Book of this very treatise, where it is stated that the ascendant and the eleventh house are in sextile to each other; the ascendant and the mid-heaven in quartile; the ascendant and the ninth house in trine; and the ascendant and the occidental angle in opposition; all which certainly seems to be applicable to mundane aspects in particular.