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What your birth hour shows
Your BaZi chart (the Chinese art of reading your birth moment) has 4 pairs of characters: year, month, day and hour. Classical books call each pair a pillar. The hour pair is the last one. It is read for your inner world: private wishes and habits that show up later in life.
Old books also tie it to children, legacy and the second half of life. Its 2 characters can add new forces to your chart and shift your mix of the five elements.
What changes without birth time
Without the time, the hour pair cannot be worked out, so 2 of the 8 characters are missing. Depending on what they hold, your element mix and the strength of your core element can read differently.
Once in a while, the hour is what brings out an element hiding inside your month's animal sign. Then the strongest force in your chart changes once the hour is known.
It is like reading a book with one chapter missing: the main story holds, some side plots stay unknown.
What stays the same
Your core element (classical name: Day Master), the element that stands for you, comes from your birth date. It never changes with the hour.
Your year and month pairs stay the same too. Your birth month sets the strongest force in your chart, so together with your day pair these 6 characters carry most of what decides your guardian.
How much is lost?
One pair out of 4, but the pairs do not weigh the same. The day pair matters most, because it holds your core element. The month pair comes next: it carries your birth season, which decides how strong each element is and which force leads. The hour pair means something, but in most readings it weighs the least.
Many readers treat a chart with 3 pairs as a fair basis for a reading.
If you do not know your birth time
Do not let a missing hour stop you. Our guide on what to do when you don't know your birth time covers ways to estimate it, and how Elemental Fate handles an unknown hour.