A Book on Celestial Learning

Section Two: On the Natures and Dispositions of the Seven Luminaries

The nature of the Sun original: 太陽 (tài yáng) is hot and dry. It is capable of heating the objects upon which it shines. The nature of the Moon original: 太陰 (tài yīn) is moist; the objects upon which it shines also receive this moisture and nourishment.

The nature of Saturn original: 土星 (tǔ xīng); literally "the Earth Star" is cold and slightly dry.

The nature of Jupiter original: 木星 (mù xīng); literally "the Wood Star" is temperate and harmonious. It is both hot and moist, though the heat is more prevalent than the moisture.

The nature of Mars original: 火星 (huǒ xīng); literally "the Fire Star" is extremely dry and extremely hot.

The nature of Venus original: 金星 (jīn xīng); literally "the Metal Star" is also temperate and harmonious. Like Jupiter, it is both hot and moist, but here the moisture is more prevalent than the heat.

The nature of Mercury original: 水星 (shuǐ xīng); literally "the Water Star" is indefinite and unstable. If it encounters heat, it becomes hot; if it encounters cold, it becomes cold. If it encounters moisture, it becomes moist, and if it encounters dryness, it becomes dry. Furthermore, it is said that Mercury belongs to the element of Air original: 氣 (qì) and generates the wind.

Key Terminology

• Seven Luminaries Seven Luminaries original: 七曜 (qī yào). The collective term for the Sun, Moon, and the five visible planets (Mercury, Venus, Mars, Jupiter, and Saturn).
• Natures and Dispositions original: 性情 (xìng qíng). The inherent elemental qualities that determine how a planet affects the Earth.
• Dryness and Moisture original: 燥/濕潤 (zào / shī rùn). These are the fundamental qualities in Aristotelian-influenced Chinese astronomy, used to explain physical changes in the environment.
• Generate Wind original: 生風 (shēng fēng). The astrological belief that Mercury's movement and position are responsible for atmospheric changes and wind patterns.