Antiscion

Meaning

A point's antiscion (plural antiscia, from the Greek anti, "opposite", and skia, "shadow") is its reflection in the axis that runs from 0° Cancer to 0° Capricorn, the solstice axis. Fold the zodiac along that line and every degree lands on its antiscion. In numbers, for a longitude λ measured from 0° Aries:

antiscion = 180° − λ

Two degrees that mirror each other in this way lie at the same distance from a solstice point, on the same side of the celestial equator. When the Sun stands on either of them it has the same declination, so the day has the same length and the Sun rises and sets at the same point of the horizon. That shared day length is the old definition: Lilly calls the antiscion signs those "equally distant" from the first degree of Cancer or Capricorn, in whose degrees the days and nights are of equal length [4]. Modern writers often call the antiscion a "solstice point" or "mirror point"; do not confuse this with the solstice points themselves, 0° Cancer and 0° Capricorn.

The mirror sign pairs are:

Within a pair the degrees run in reverse, adding up to 30°: 27° Taurus mirrors 3° Leo, 10° Taurus mirrors 20° Leo (Lilly's example [4]), 15° Gemini mirrors 15° Cancer.

The counting pitfall. Subtract the whole position, minutes included, from 30°. Lilly's Saturn at 20°35′ Leo has its antiscion at 30°00′ − 20°35′ = 9°25′ Taurus [4]. Old whole-degree tables need care. Firmicus pairs the 1st degree of Gemini with the 29th of Cancer and the 15th with the 15th, and says the 30th degree is paired with none [2]; al-Bīrūnī pairs degrees the same way (the 1st of Aries with the 29th of Pisces, the 10th with the 20th) [3]. Read as positions (1°00′ Gemini, 29°00′ Cancer) these are exact; read as ordinal degrees (the "1st degree" being 0°–1°) they are off by one. The safe rule is always 180° − λ.

A planet on another's antiscion is joined to it much as if by aspect, and the link runs both ways: if A is on B's antiscion, B is on A's.

Origin and history

Ptolemy's chapter does not use the word, but it describes the relationship. Parts of the zodiac equally removed from the same tropical sign are "of equal power", since the Sun in either gives equal days, nights and hours, and they "behold" one another because they rise and set at the same part of the horizon [1] (see signs of equal power). Robbins's notes read these pairs as whole signs balanced around Cancer and Capricorn (Gemini with Leo, Taurus with Virgo), not the antiscion sign pairs above [1].

Firmicus Maternus, in the 4th century, gives the fullest early account, the chapter "De antisciis" of the Mathesis [2]. He calls the doctrine Greek, citing Ptolemy, Antiochus and the fourth book of Dorotheus [2]. After the sign pairs and degree table he adds an extension (II.29.9): planets that do not see each other should be checked for a trine, square, opposition or sextile through the antiscion, which then acts as if the aspect were direct [2]. His example is the chart of an unnamed Roman official whose father was exiled after two consulships; he tells his dedicatee Lollianus that he knows very well whose chart it is [2]. Theodor Mommsen proposed in 1894 that the native was Ceionius Rufius Albinus, prefect of Rome in the 330s, and Otto Neugebauer later found that the planetary positions fit a birth date of 14 March 303 [5].

Al-Bīrūnī (1029) calls signs equidistant from a solstice "corresponding in course": they revolve on the same parallel, with equal day hours and equal night hours [3].

William Lilly brought the doctrine into English with a sign table, the subtract-from-30 rule and a reckoner in degrees and minutes. A planet's antiscion, he says, gives influence to any planet or star in that degree or aspecting it, and antiscia of the good planets count as a sextile or trine [4].

Placidus (1657) went a step further. He renamed antiscia "parallels" and counted two bodies as being in antiscion only when they actually have the same declination, taking their latitude into account [6]. This is the root of the modern declination parallel.

How it is used

Natal charts. Antiscia reveal hidden ties between planets with no aspect between them. Firmicus uses them to explain events the plain aspects did not show [2].

Horary. Lilly teaches antiscia in the introduction that opens Christian Astrology and uses them in his own horary judgments in Book II, for instance noting when a planet's antiscion falls on a house cusp or on the ascending degree [4].

Orb. The old authors give no orb; Firmicus works by degree, Lilly to the minute [2] [4]. Modern orbs vary and are usually small; this site uses 1° by default.

On this site. The Antiscia panel uses 180° − longitude for the planets, the Moon's Node, the Ascendant and Midheaven (with a known birth time), optionally the 2nd, 3rd, 5th, 6th, 8th, 9th, 11th and 12th cusps, the seven Hermetic lots plus any lot added by search, and the 15 Behenian stars. Stars are not paired with stars, lots with lots or cusps with cusps. The orb runs from 0.25° to 2° (1° by default), and each contact is listed once per pair. An option adds Firmicus's aspects to the mirror point: sextile, square, trine, and opposition when the equinox axis is off (the opposite of the antiscion is the contra-antiscion). A last column says whether the pair is also a declination parallel, which a point off the ecliptic, such as the Moon or a star, may not be. On the wheel 0° Cancer is at the top, so every antiscion contact is a level line.

Examples

• Einstein's Sun is at 353.508°, 23°30′ Pisces. Its antiscion is 180° − 353.508° = −173.508°, that is 186.492°, or 6°30′ Libra.
• Through the mirror. In the same chart (14 March 1879, Ulm, 11:30 local mean time) Mercury at 3°09′ Aries has its antiscion at 26°51′ Virgo. Mars at 26°55′ Capricorn is trine that point, about 3′ from exact: an antiscion trine in Firmicus's sense.
• The pitfall. A planet at 27°40′ Taurus sends its antiscion to 2°20′ Leo, not 3°40′.