《明史·志·卷七》
十四日昼夜已经平分，那么新历法推算十四日为春分符合天象，而旧历法推定为十六日，已落后天象二日了。
夫十四日书夜已平分，则新法推十四日春分者为合天，而旧法推十六日者，后天二日矣。
Day and night are already equal on the 14th, so the new calendar's calculation of the 14th as the vernal equinox conforms to celestial phenomena, while the old calendar's determination of the 16th as the vernal equinox is two days behind celestial phenomena.