Saju Basics — How to Read Yourself Through Heavenly Stems, Earthly Branches, and the Five Elements
About 8 min read
Saju (四柱八字, the Four Pillars of Destiny) is the heart of Myeongni, the East Asian art of fate that has been passed down for over a thousand years. As the name suggests, it means 'four pillars (四柱)' and 'eight characters (八字)': it translates the moment of a person's birth into symbols to read their innate temperament and the flow of their life. It can feel intimidating, but once you grasp a few basic concepts, anyone can read the big picture of their own chart.
Saju is time rendered as symbols
Saju is not a mystical prophecy but a table that records four units of time — the year, month, day, and hour of your birth — as two characters each, eight characters in all. The old Eastern calendar marked each day, month, and year with 'ganji (干支),' a cyclical notation of sixty stem-and-branch pairs, and Saju simply draws the four cells corresponding to the moment you were born from that very calendar. That is why casting a Saju is called 'setting up a chart,' and the precise calendar it rests on is called the Manseryeok (the perpetual calendar).
Ten heavenly stems and twelve earthly branches
The eight characters are made of two kinds of symbols. The top row is the 'Cheongan (天干),' the ten heavenly stems — Gap, Eul, Byeong, Jeong, Mu, Gi, Gyeong, Sin, Im, Gye — and the bottom row is the 'Jiji (地支),' the twelve earthly branches — Ja, Chuk, In, Myo, Jin, Sa, O, Mi, Sin, Yu, Sul, Hae. The twelve branches pair with the twelve zodiac animals we know, such as the rat, ox, and tiger. If the heavenly stems represent the energy of heaven — the tendencies and mind that show on the surface — then the earthly branches represent the energy of earth: the concrete foundation, inner feelings, and environment.
How the four pillars are built
The year pillar (年柱) marks the year of birth, the month pillar (月柱) the month divided by the solar terms, the day pillar (日柱) the day of birth, and the hour pillar (時柱) the hour divided into two-hour units — each shown as a single pair of ganji. Two things deserve attention here. First, the boundary of a month is set not by the first of the solar-calendar month but by the twenty-four solar terms, such as Ipchun and Gyeongchip. Second, if you don't know your birth hour, most readings are still possible using the three pillars without the hour pillar. So for an accurate chart, your birth date matters, and where possible your birth hour, along with whether the date is lunar or solar.
The Day Master — the 'self' at the center of the chart
The single most important character among the eight is the heavenly stem of the day of birth, the 'Day Master (Ilgan, 日干).' The Day Master symbolizes 'you yourself' in the chart, and all seven remaining characters are interpreted in relation to it. For example, if the Day Master is 'Gap (甲),' the person is seen as born with the energy of a great tree, read as upright and inclined to reach upward. When you first look at your own Saju, the whole picture becomes far clearer once you check what your Day Master is and which of the Five Elements it belongs to.
The balance of the Five Elements and body-strong versus body-weak
Each of the eight characters belongs to one of five energies: Wood (木), Fire (火), Earth (土), Metal (金), and Water (水). A major axis of reading a Saju is seeing how evenly, or how lopsidedly, these five energies are distributed. When the energies that support the self (the Day Master) are plentiful, the chart is 'singang (身強, strong self)'; when the energies that drain the self are plentiful, it is 'sinyak (身弱, weak self)'; either way, the element that fills and regulates whatever is lacking or excessive is called the 'yongsin (用神, the useful god).' Knowing your yongsin is a practical key to knowing which colors, directions, and lines of work suit you.
One worked chart — May 15, 1990, 10:30 in the morning
Once you know the principles, the quickest way to learn is to set up a real chart. For someone born on May 15, 1990, at 10:30 in the morning, this site's perpetual calendar gives the four pillars, from year to hour, as 庚午·辛巳·庚辰·辛巳. The year pillar is 庚午 because that year's Ipchun (February 4) had already passed, and the month pillar is 辛巳 because the 巳 month runs from Ipha on May 6 until just before Mangjong on June 6. This is exactly where counting May as the fourth month from the solar calendar alone would go wrong. The hour pillar 辛巳 comes from the 巳 hour, which in standard time runs from 9 a.m. up to 11 a.m.
Naming the other characters from the Day Master
The Day Master of this chart is 庚, yang metal (陽金), often likened to hard, unworked iron. The seven other characters are all named by the relationship they hold with this 庚, and those names are called the ten gods (十神). The year stem 庚 shares the Day Master's own energy, so it is a Companion (比肩), while the 辛 in the month and hour stems is the same metal with the opposite polarity, which makes it a Rival (劫財). Branches are read through the main stem hidden inside them, so the year branch 午 is a Direct Officer (正官), the 巳 in the month and hour branches is Seven Killings (偏官), and the day branch 辰 is an Indirect Resource (偏印). With the names in place, you can see at a glance that the chart runs along two lines: forces on your own side and forces that press on you.
Counting characters is not the same as weighing strength
Counting the eight characters by element alone gives 金 4·火 3·土 1·木 0·水 0. This site, however, also weighs the stems hidden inside the branches (jijanggan) and the weight of each position, and reports the strength of each element as a percentage. Measured that way the chart reads 金 55.8%·火 22.1%·土 17.1%·木 3.8%·水 1.3%, so Wood and Water, absent as characters, surface in small amounts from the hidden stems. Strong or weak is judged by how much the seven positions other than the Day Master itself support it, and this site calls a share of 50% or more strong and 65% or more very strong. This chart's supporting share is 66%, so it is Very Strong (太強), yet the 巳 month belongs to the season of fire, so it does not have the month's command (月令); its strength comes from the day branch 辰 and the many metal characters.
Eokbu and johu — where the useful element splits
A chart with excess energy usually takes as its yongsin an element that drains or restrains that excess, and this method is called eokbu. Read by eokbu (抑扶) alone, this chart would point to Fire (火), which melts and governs the surplus metal, as the yongsin candidate. But the person was born in the 巳 month, a summer month, and when only the seven positions other than the Day Master are weighed, the Water that would cool the heat is just 2%, so this site follows johu (調候), which settles the season's temperature first, and raises Water (水) to yongsin and Metal (金), which feeds Water, to heesin. The site's rule is that johu overrides eokbu when, measured this way without the Day Master, Water falls below 10% in summer or Fire falls below 10% in winter (so the figure can differ slightly from the element bars on screen, which include the Day Master), while in spring and autumn, where schools prescribe differently, eokbu stands as it is. Knowing that the same chart can get a different yongsin depending on the school will make it less confusing to compare readings from other sources.
Ipchun and the Rat hour — two boundaries where schools part
In Saju the year changes at Ipchun, not on January 1 and not at the Lunar New Year. So someone born on February 1, 1990, is a Horse by zodiac animal because that year's Lunar New Year (January 27) had already passed, yet their Saju year pillar is still the previous year's 己巳 because Ipchun had not arrived. This site's Chinese zodiac reading splits your birth-year animal at the Lunar New Year (the “this year” it reads your fortune for turns at Ipchun, as in Saju) while the Saju year pillar splits at Ipchun, so almost every year there are birth dates for which the two pages show different animals. Schools also disagree on where a day ends, and this site follows the late-Rat-hour (yajasi) method, which treats 11 p.m. to midnight as the next day's Rat hour while leaving the day pillar on the calendar day. Had the person in our example been born at 11:30 p.m. on the same day, the day pillar would stay 庚辰 and only the hour pillar would follow the next day's stem, becoming 戊子.
Three common misunderstandings
The first is the idea that people who share a zodiac animal have similar charts. The animal usually corresponds to just one of the eight characters, the year branch, so even people born in the same year end up with entirely different charts when their Day Master and season differ. The second is the belief that entering the lunar birthday is more accurate, but whether you enter the solar or lunar date, as long as it points to the same moment the perpetual calendar produces the same eight characters. The third is the notion that there are good charts and bad charts. Myeongni is a system for reading where the energies lean and how to use that lean, so even a lopsided chart has a way to put its lean to work.
The classics behind Ziping astrology
The theory of Ziping astrology, named after Xu Ziping (徐子平), spread widely through the Ming-era compilation Yuanhai Ziping (淵海子平). The Ditian Sui (滴天髓), which deals with the flow and strength of the energies, and the Qiongtong Baojian (窮通寶鑑), which sets out the johu theory of choosing the yongsin by the heat or cold of the birth month, are also often quoted as roots of today's readings. The singang–sinyak judgment and eokbu yongsin used on this site are the standard methods of the Ziping lineage, and its summer–winter johu rule is a simplified form of the seasonal prescriptions the Qiongtong Baojian emphasizes. Because the classics sometimes read the same chart differently, it is better to ask which method from which book a reading rests on than to treat any single reading as the answer.
Saju is not a verdict announcing a fixed fate; it is closer to a map that reads the tendencies of your innate temperament and life's flow so you can handle yourself better. Now that you have the broad framework, set up your actual chart from your own birth date and check your Day Master, Five Elements, and yongsin for yourself.