Decan 3 of Pisces

This is the third ten-degree segment of Pisces, the mutable water sign, spanning 20 to 30 degrees, and the last of the thirty-six decans, closing the zodiacal circle. Its ruler in the Chaldean order of faces is Mars; because thirty-six is not a multiple of seven, the sequence of the seven planets, run five times around the wheel from Mars at zero Aries, closes exactly here at the end of Pisces, an elegance that helped fix the scheme. The decan is the oldest layer of astrology, the thirty-six having begun as Egyptian star groups used to divide the year and the night.

The Golden Dawn, from 1888, mapped the numbered minor cards onto the decans; this final segment carries the Ten of Cups, titled Satiety or Perfected Success, its Mars-in-Pisces attribution taken from the face ruler, the tens completing the water suit with the card of fulfilled emotional happiness. That tarot layer is a modern Western overlay on the ancient decan scheme rather than part of the inherited tradition.

The third decan of Pisces runs from 20 to 30 degrees of the sign and is ruled, in the scheme this atlas records, by Mars.

The card on the decan

In the Golden Dawn's assignment this decan carries the Ten of Cups. The mapping is one to one and exhaustive: the thirty-six small cards numbered two to ten across the four suits match the thirty-six decans exactly, taken in order from the Two of Wands at the first decan of Aries. The suit follows the sign's element, so Pisces is a Water sign and takes a card of Cups, and the rank follows the position in the sequence, which puts the ten here.

Why the rulers carry over between signs

The thirty-six rulers run in the Chaldean order, the seven planets arranged from slowest to fastest as Saturn, Jupiter, Mars, Sun, Venus, Mercury and Moon, applied one after another right round the circle beginning with Mars at the first degree of Aries. Because thirty-six is not divisible by seven, the sequence does not restart at each sign. It runs straight through the boundaries, which is why the rulers of a sign's three decans are not the sign's own planets and why the pattern only closes after the whole zodiac.

What the atlas is recording

The degrees and the ruler are the attributions this atlas holds for this decan, and the card is the Golden Dawn's. All of them are traditions with variants rather than settled facts, and the decan itself, as a ten degree segment of a sign, is the only part that is simply arithmetic.