Wake Forest University

UTF Traditional:

30

天 明 ， 則 日 月 不 明 。 天 無 明 。 夜 半 黑 淬 淬 地 ， 天 之 正 色 。 僩 。

UTF Simplified:

天 明 ， 则 日 月 不 明 。 天 无 明 。 夜 半 黑 淬 淬 地 ， 天 之 正 色 。 □ 。

big5:

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GB:

�� �� �� �� �� �� �� �� �� �� �� �� �� ҹ �� �� �� �� �� �� �� ֮ �� ɫ �� �� ��

Translation:

When the sky is bright, then the sun and the moon are not bright. When the sky has no brightness, in the middle of the night when it is pitch black, then that is the true color of heaven.
Xian

Commentary:

In many other passages, Zhu Xi has shown himself to be an accurate observer and a sensible theorizer in the field of natural science. This passage, however, simply does not make sense. My guess is that bad note taking by someone who did not have a good understanding of common natural phenomena was at fault.

When the sun is bright in the sky, the sky is bright, and the moon, although it may be visible, is not easily seen. As the sun sets, the moon and stars become progressively more easily seen because there is less contrast between the light from the sky and the light from the celestial objects. So the first sentence should be fixed by removing the word "sun."

The accurate observation that this passage reports is that the color of the daytime sky is the result of light from the sun.

-- PEM