The three branches of Jyotish

Classical Jyotish divides into three skandhas, or branches. Learners often skip this and go straight to chart reading, which is a mistake: the division tells you what kind of question each technique was built to answer.

1. Siddhanta — the mathematics

Siddhanta (also called Ganita, calculation) is astronomy proper. It computes where the planets are, predicts eclipses, and produces the panchang.

This is the branch with a genuine, verifiable track record. Classical Indian astronomers modelled planetary motion to real precision, and eclipse predictions from these methods can be checked against the sky — they either happen at the predicted time or they do not.

Everything else in Jyotish depends on this branch being right. An interpretation built on a wrong planetary position is wrong no matter how skilled the interpreter. This is exactly why the calculators on this site are held to a golden-test suite before they go live: if the arithmetic is off, nothing above it can be salvaged.

2. Samhita — the collective

Samhita is mundane astrology: the fortunes of groups rather than individuals. Weather and monsoon, harvests, earthquakes, comets, the fate of kingdoms, omens.

Varahamihira's Brihat Samhita is the great text here, and its range is startling. Alongside planetary omens it covers architecture, town planning, the testing of gemstones, perfumery, hydrology and the treatment of plants. Read as an encyclopedia of sixth-century Indian practical knowledge it is remarkable, whatever one makes of its astrological claims.

Samhita is the branch that has faded most in modern practice. Almost nobody consults an astrologer about the monsoon any more.

3. Hora — the individual

Hora is the predictive branch concerned with persons, and the one nearly everyone means by "astrology". The word is the Greek hōra, and it is also the root of horoscope.

Hora subdivides further, and these subdivisions matter because they answer genuinely different questions:

• Jataka — natal astrology. A chart cast for a birth. "What does this life look like?" This course is almost entirely Jataka.
• Muhurta — electional astrology. Choosing an auspicious moment to begin something: a marriage, a journey, a business. "When should I do this?" Still very much alive in Indian practice.
• Prashna — horary astrology. A chart cast for the moment a question is asked, not for a birth. "What about this, right now?" Especially useful, in the tradition's own terms, when the birth time is unknown — which historically it very often was.

Some classifications add Nimitta, the reading of omens, and some fold it into Samhita instead. The boundaries are not policed.

Why the division matters to you

Two practical consequences.

First, techniques are not portable across branches. A rule for judging a natal chart is not a rule for choosing a wedding date, even when the same planets are involved. Beginners mix these constantly.

Second, when someone claims astrology "works", ask which branch they mean. Siddhanta demonstrably works — it predicts eclipses. That says nothing whatsoever about Hora, which is a separate claim requiring separate evidence. Conflating the two is the most common rhetorical move in defences of astrology, and it is worth being able to spot.