Saju (四柱) means, quite literally, "four pillars." Here, the four pillars are the year, month, day, and hour in which a person was born. In the East, time has long been seen not as mere numbers but as a flow that each carries its own distinct energy, and that energy of time was expressed through combinations of the ten Heavenly Stems (the energy of heaven) and the twelve Earthly Branches (the energy of earth). So each of the year, month, day, and hour pairs one Stem with one Branch, producing eight characters in all—this is saju palja, the "four pillars, eight characters."
These eight characters are like a photograph that captures the energy of the moment a person came into the world. In particular, the Heavenly Stem of the birth day is called the "day master," taken as the center symbolizing the person themselves; by examining how the remaining characters relate to the day master, one reads personality and talent, the texture of relationships, and the flow of wealth and work. The yin-yang and five elements we looked at earlier form the very basis of this interpretation, gauging which energies overflow and which are lacking within the eight characters.
The most common way to misunderstand saju is to receive it as a "fixed script of the future." But saju is not a tool that nails down fate; it is closer to a map of one's innate temperament and a weather forecast of time. Holding the same map, which road each person takes differs, and hearing the same forecast, the day of one who brings an umbrella differs from one who does not. What saju tells you is less "this is how you will turn out" and more "you were born with this kind of energy, so it would be good to make the most of times like these and take care in times like those."
So studying saju leads to understanding yourself more deeply, filling the energies you lack through how you live, and the wisdom not to miss a good current when it arrives. Counseling warmth to one who needs cold resolve, and patience to one who rushes too much, saju is in the end advice toward balance. FortuneLeaf's saju content, too, does not stop at difficult character glosses; it takes care to carry the story those eight characters offer to the you of today into warm, living language.
The word saju (四柱) literally means "four pillars." The year, month, day, and hour of birth each become a pillar, and in every pillar a Heavenly Stem—a character expressing the energy of the sky—pairs with an Earthly Branch—a character expressing the energy of the earth. So the four pillars hold two characters each, eight in all, which is why it is often called "the eight characters of the four pillars." There are ten Heavenly Stems (jia, yi, bing, ding, and so on) and twelve Earthly Branches (zi, chou, yin, mao, and the rest—the same twelve as the familiar animal signs); the sexagenary cycle in which these two mesh and turn forms the rhythm of time. Most important of all is the Heavenly Stem of the birth day—the "day master." When reading a saju, this day master is taken as "the self," and one reads how the remaining seven characters relate to it. Even a reading that looks complex begins, in the end, from gauging the harmony and balance of the energy that flows among these eight characters.