The 24 solar fortnights, èrshísì jiéqì 二十四節氣, trace their roots to the monthly ordinances (yuèlìng 月令) first described in the Book of Rites (Lǐ jì 禮記), reflecting astronomical observations dating as far back as 620 BCE. The 24 solar terms or “solar fortnights” form the backbone of the traditional Chinese calendar. These subtle seasonal markers reflect the movement of the sun through the heavens, dividing the year into precise phases of climatic and energetic change. Each fortnight carries its own character, its own qi, and its own message about how life moves and transforms.

Dividing the year into 24 equal parts — each of 15 days — this calendar maps the cycle of the sun (tàiyáng 太陽) and its influence on the Earth with extraordinary precision. The 360 days of the traditional year correspond not only to time, but to space — echoing the circle of 360 degrees. The annual journey of the sun becomes a cosmic dance of qi, time, light, and life.

春生, 夏長, 秋收, 冬藏, 是氣之常也, 人亦應之
Spring engenders, summer flourishes, autumn harvests, winter stores.
This is the constancy of qi — and humans, too, resonate with it. (Lingshu 44)

Each jieqi (solar node) describes a unique phase in the unfolding breaths of Heaven and Earth — seen in changes in temperature, weather, plant growth, animal behaviour, and the rhythms of the body. From snow melting and insects stirring, to the ripening of grain and the arrival of frost, the jieqi offer a living dialogue between the cosmos and human life.

This agricultural calendar has been used for millennia in farming, ritual, and medicine. In Chinese Medicine, the jieqi are not just seasonal markers but energetic touchpoints — windows into how qi moves and transforms throughout the year. By following these fortnights, practitioners can attune to the larger rhythms of nature, aligning treatment strategies with seasonal energies to enhance health and resilience.

In this course, Deborah guides you through the 24 solar terms, exploring their meanings through classical texts and cosmological principles. Each fortnight is linked to specific acupuncture channels, lifestyle guidance, and clinical insights — helping you bring this ancient wisdom into modern practice.

By living in harmony with the jieqi, we deepen our connection with the Dao, become more attuned to change, and support ourselves and our patients in moving smoothly through the cycles of the year.