Saju and Western astrology, compared piece by piece

What is saju if you already read a birth chart?

Saju (사주), the Korean reading of the four pillars of birth, is built from the same facts a birth chart is: the date, the clock time and the place. It turns them into eight Chinese characters instead of planetary positions, and nothing in it is a planet. A birth chart records where the bodies of the solar system stood at your first breath. Saju records where that breath fell inside a calendar, one that divides the sun's year at twenty four marked points and counts days in cycles of sixty.

That leaves one honest point of contact and a long list of differences. The point of contact is the sun. Your tropical sun sign measures where the sun sat on its yearly path, and so does the month pillar of a saju chart, which is why those two never drift far apart. The houses, the aspects, the moon and the retrogrades have no counterpart in saju, and saju carries two or three things with no counterpart in a birth chart. If the whole idea is new, the beginner page comes first.

What plays the part of the birth chart?

The four pillars. Year, month, day and hour each get a pillar, and each pillar holds two characters, a heavenly stem above and an earthly branch below. Eight characters, the entire chart. Ten stems and twelve branches turn together like two gears of different sizes, so a full round of pairings takes sixty steps before repeating.

The month boundary is where readers who know astrology usually sit up. Saju months do not change on the first of the month. They change at the twelve sectional solar terms, which are fixed points on the sun's path rather than dates. Ipchun, the start of spring, arrives when the sun reaches fifteen degrees of Aquarius, around 4 February, and opens both the saju year and its first month. Every month after it begins near the middle of a tropical sign, not the start of one. Someone born on the March equinox is not in a fresh month pillar; theirs opened in mid Pisces two weeks earlier.

The hour pillar needs a real clock time, corrected first for Korea's longitude and for the daylight saving it ran in several stretches of the twentieth century. If your birth time was never recorded, a chart can still be read from seven characters, which the page on unknown birth times goes through.

What plays the part of the sun sign?

Two different things do, and separating them is most of this page. The single character that stands for you is the day master, the stem of your day pillar. The one carrying the weight your sun sign carries is the month pillar, because the month is the season. People are usually handed the first and told it is the second.

The day master (일간) is one of ten stems: Gap (甲), yang wood, Eul (乙), yin wood, on through Im (壬), yang water, and Gye (癸), yin water. Ten of them, not twelve, and they come from the day, not from the sun's yearly position. Two people born a day apart in the same city share a sun sign and have different day masters.

The deeper difference is in how each one is read. A sun sign is written up as a character sketch that stands by itself. Gap alone says very little. Gap is a tall growing tree, and what matters is where that tree stands. Gap in spring, water near it and a little fire above, is a tree in a kind year. The same Gap in late autumn, surrounded by metal, is a tree in a season that cuts. The stem has not changed and the reading has, because a day master is a position in a field rather than a label on a person. The Gap page works through one of the ten, and how to read your chart shows where the day master sits among the other seven characters.

One more thing gets mistaken for a sun sign. The Korean zodiac animal is the branch of your year pillar, one character out of eight, and the piece a reader leans on least for an individual. Born before ipchun, you carry the previous year's animal, which is why online lists and Korean readers sometimes disagree.

What maps to what?

What plays the part of transits?

Saju has two moving layers, behaving like two different Western techniques. The yearly cycle (세운) is the closest thing to a transit. Each year has its own stem and branch, 2026 being Byeong-o, yang fire over the horse, and that pair is the same for everyone alive. It is read for what it meets in your eight characters, so a year that presses hard on one chart passes quietly over another.

The ten year cycles (대운) have no transit analogue, and readers of traditional Western astrology will recognise them as a time lord system instead. They are counted out of your own month pillar, forwards or backwards depending on the polarity of your year stem and your sex, and the starting age comes from how far your birth stood from the neighbouring solar term. Two people born on the same day in the same hospital can run opposite sequences, and this is usually the layer that explains why a stretch of years felt as it did. The luck cycles page goes through the counting.

Both layers describe weather rather than events. A cycle bringing more water to a chart already heavy with water is read as a stretch to watch for drift, and the useful part is what to do about it. Timing and tendency are what the method gives. Outcomes are not on offer.

Why is there no house, aspect or retrograde in saju?

Because saju never looks at the sky. The eight characters are calendar positions, and a calendar has no horizon to divide into houses, no two bodies to hold an angle between, and no apparent backward motion to observe. The vocabulary has nowhere to attach.

The work those techniques do still gets done, by other means. Houses parcel out areas of life; saju does that through the ten gods, which name each of the other seven characters by its relation to the day master, so one becomes the wealth relation and another the authority relation. Aspects describe two placements pulling on each other; saju uses combinations and clashes, which are fixed lists of pairs. Sin (申) and hae (亥) do a particular thing when they meet. It is a lookup, not a measurement.

One confusion is worth heading off. In Korean the five visible planets are named after the five elements, so Jupiter is the wood star and Mars the fire star. The names overlap; the practice does not, and saju never uses where Jupiter is. The symbolic stars called sinsal (신살) are a separate tradition, and not stars either, as that page explains.

Saju is also not the sidereal system used in Vedic astrology. Saju has no zodiac belt at all, in either the tropical or the sidereal sense. Its twelve branches divide time, and the animals attached to them are a mnemonic, not constellations.

What does a birth chart not have?

Two things, mainly, and they are what make saju worth the trouble if you already have a chart you like.

The first is the five elements used as a working balance. Western astrology has four elements and most astrologers count them, noting a chart heavy in water or short on air, and traditional practice reads temperament from them with care. Saju goes further, because its five are wired together by two fixed relations. Each produces the next, water feeding wood, wood feeding fire, and each controls another, metal cutting wood, fire melting metal. That wiring turns a count into a diagnosis: what the chart has too much of, what it lacks, and the one element that would settle it, which is the question a Korean reader spends most of a reading on. The balance page sets out how that judgement is made.

The second is the weight put on the season. The month pillar is the heaviest of the four, because the season decides whether your day master stands in supportive ground or thin ground, and the rest is read against that. Tropical signs are seasonal too, so the information sits in a birth chart, but nothing there uses the season to grade the strength of everything else. Essential dignity is the closest thing, and a real cousin rather than a stretch.

Neither list makes one practice better than the other. They are different instruments, and a good many of my clients keep both. They sit side by side most comfortably in compatibility, since synastry and Korean gunghap (궁합) ask similar questions of two charts from different material, which the gunghap page covers.

What can this page not tell you?

Anything about your own eight characters. Everything above is the general shape of the method, and a general shape is what a saju reading is not. The same day master reads one way beside two waters and another beside none. The season changes it, the hour changes it, the cycle you are in changes it again, and no single piece settles which element your chart wants.

At Mulsangjae the whole chart is set down as one landscape, and what I found is written out at length, usually around fifty pages. The painting is not decoration; it is how the balance of a chart becomes one image you can hold in mind, which the page on the image explains, and you can look through a sample first. Reports are written in Korean at present and the English edition is in preparation, so readers who want one join the waitlist.

Common questions