The "fen" in autumn equinox means to divide equally. During this time, the sun shines almost directly on the Earth's equator, creating equal day and night across the globe. Additionally, it bisects the autumn season, sitting precisely in the middle of autumn's ninety days, serving as the watershed between early and deep autumn.

This miraculous balance also finds its perfect expression in Beijing. This line is Beijing's central axis, with the Imperial Ancestral Temple honoring ancestors on the left and the Altar of Earth and Grain venerating the land on the right. From palaces to marketplaces, from altars to bell towers, the architectural complexes on both sides of the central axis are perfectly symmetrical, embodying the symmetrical aesthetics deeply rooted in Chinese culture.

This line traverses history and connects with the cosmos. Just as the autumn equinox divides day and night equally, Beijing's central axis divides the entire landscape of mountains, rivers, and the passage of time.