Meaning
A trine is a third of the circle, the side of an equilateral triangle drawn inside the zodiac. Counted by signs it joins signs four apart, which always share their element: Aries, Leo and Sagittarius; Taurus, Virgo and Capricorn; and so on round the four triangles. Ptolemy's triplicities, with their lords, are the same triangles, and Valens names them by element. He counts the trine harmonious, the greater of the two easy aspects.
The tradition reads the trine as the easiest connection between two bodies: natural talent, support, things that come without effort. Modern astrology calls it soft, and names its shadow as complacency, ease that is never put to use. Our readings call it ease, never good fortune.
Our orbs
We allow 10° when the Sun or Moon is in the pair and 8° otherwise, and half that to Chiron, the North Node and the angles. A trine within a quarter of a degree is marked exact. Our chart draws trines with long dashes, sextiles with short ones, so that soft aspects show by pattern as well as by colour.
A trine can also be "out of sign", 120° by degree between signs that are not four apart, when one body sits at the end of a sign and the other at the start of one; we count it by degrees, as most tools do, while CHANI and the whole-sign schools would not.
Other schools
Kepler, in his Harmonices mundi of 1619, built the aspects on the ratios of the circle and kept the trine among them. The idea that each aspect is a musical interval, the trine a fifth, is a modern table, not his or Ptolemy's. In Jyotisha, Jupiter's special aspects fall on the fifth and ninth signs from it, the trines counted by sign.
Correspondences
Each item with how it stands: “sourced” is in the work cited, “our construction” is EsoTerrier’s own, and “disputed” means the sources disagree.
- Angle (Ptolemy)
- 120° sourced
- Class (Ptolemy, in Ashmand)
- harmonious sourced
- Modern class
- soft or easy sourced
- A musical interval
- A modern table; Kepler built aspects on harmonic ratios in 1619, Ptolemy on halves and thirds of the circle disputed
- Invented by Ptolemy
- No: in use before him; "Ptolemaic" records his later authority disputed
- One standard orb
- No: orbs differ by school disputed
- Our orbs
- 10° with the Sun or Moon, 8° otherwise, half to the points our construction
How the schools read it
- Ptolemy (2nd century CE)
- Harmonious: it joins signs of the same kind.
- astro.com default
- 10° for every pair, points at half.
- astro.com classical style
- Orbs by planet: luminaries 9°, Mercury, Venus and Mars 7°, the outer planets 5°.
- CHANI
- Aspects counted by whole sign, not by degree.
- Kepler (1619)
- Built the aspects on harmonic ratios and added the quintile, biquintile and sesquiquadrate.
- Jyotisha
- No aspects by degree: each graha aspects the seventh sign from it, and Mars, Jupiter and Saturn further signs.
- EsoTerrier
- 10° with a luminary, 8° otherwise; applying or separating; called easy.
Claims about it
-
Ptolemy invented the five major aspects, which is why they are called Ptolemaic.
disputedWhat the record shows: He lists the configurations, but the aspects were in use before him and Valens uses them without crediting him; "Ptolemaic" records his later authority, not an invention.
-
One set of orbs, such as 10° for every aspect, is the standard.
disputedWhat the record shows: Orbs differ by school: Lilly gave each planet its own; astro.com's default is a flat 10°, 6° for the sextile; others scale by planet; CHANI counts by sign. Ours are printed with every chart.
-
Each aspect is a musical interval, and the aspects come from the monochord.
disputedWhat the record shows: Ptolemy derives the aspects from halves and thirds of the circle and calls the trine and sextile harmonious because they join signs of the same kind; Kepler built them on harmonic ratios in 1619. The aspects came first, and the table of intervals is a modern construction.
