The lake gives up depth so the mountain can rise: a hexagram of cutting back, where reduction works only when it is sincere and aimed at what should go.
Gen ☶, mountain, whose quality is stopping, stands above Dui ☱, lake, joyful. Zhu Xi reads the figure as the lower trigram giving its top line to the upper one, so that the lake grows shallower and the mountain higher: those below giving to those above. Everything depends, for him, on cutting what ought to be cut and doing it with sincerity; then even a plain offering of two bowls is enough.
Judgment (卦辭)
The text attached to the whole hexagram, read when no line is changing.
損，有孚，元吉，无咎，可貞，利有攸往。曷之用，二簋可用享。
Sun: with sincerity, great good fortune and no blame. One can stay correct and firm. It is favorable to have somewhere to go. What should be used? Two bowls can serve for the offering.
Zhu Xi explains the figure as the lower trigram giving up its top yang line to the top of the upper trigram: the lake made shallower so the mountain can stand higher, below giving to above, inner to outer. He also calls it the picture of taking from the people to serve the ruler, which is why everything hangs on the conditions: cut what ought to be cut, and do it with sincerity. Then the four favorable responses follow. As for the two bowls, in a time of reduction even the plainest offering does no harm.
Image (大象)
The Image commentary (象傳) reads the whole hexagram from its two trigrams.
山下有澤，損。君子以懲忿窒欲。
Below the mountain there is a lake: Reducing. The noble person curbs his anger and blocks his desires.
A lake lies at the foot of a mountain, its depth giving way to the height above. Zhu Xi's note is that of all the things a person cultivating himself should cut back, none is more pressing than these two. Reduction here starts at home, with one's own temper and wants.
Lines (爻辭)
From the bottom line to the top. In the line names, nine (九) marks a yang line and six (六) a yin line.
Line 1, yang (初九)changing line in the shared reading
已事遄往，无咎，酌損之。
Set aside your own affairs and go quickly: no blame. Weigh how much to take from yourself.
In a season when those below give to those above, the first line (初九) has a partner in the fourth. Zhu Xi reads the text as dropping one's own work to hurry to that partner's aid, which carries no blame. He adds the caution in the last words: someone in a low place who gives upward should still weigh how much to give. Generosity has a measure.
Line 2, yang (九二)changing line in the shared reading
利貞，征凶，弗損益之。
It is fitting to stay correct and firm. Setting out brings misfortune. Without reducing itself, it brings increase.
The second line (九二) is strong and central, and it intends to hold its ground instead of rushing forward. That is why the text favors steadfastness and warns against setting out. Zhu Xi reads the last phrase as the line's real contribution: by not changing what it holds to, it already benefits those above. Not everything useful requires giving something up.
Line 3, yin (六三)changing line in the shared reading
三人行則損一人，一人行則得其友。
Three people setting out together lose one. One person setting out gains a friend.
Zhu Xi explains the arithmetic through the figure. The lower trigram began as three yang lines; one left to go up, so three travelers lose one. As that yang goes up and a yin comes down, the lone traveler gains a friend. Two together stay focused, he says, while three grow mixed and muddled, and he reads the third line (六三) as a call to single-mindedness.
Line 4, yin (六四)changing line in the shared reading
損其疾，使遄有喜，无咎。
Reducing its ailment. Make it quick, and there is joy. No blame.
The fourth line (六四) is yin, and Zhu Xi treats its softness as the ailment to be reduced. The cure comes from its partner, the strong first line, which hurried to its aid. Only speed makes this work well: accept the help quickly, and there is cause for joy, without blame. A fault with a remedy at hand is best not left waiting.
Line 5, yin (六五)changing line in the shared reading
或益之十朋之龜，弗克違，元吉。
Someone adds to it a tortoise worth ten pairs, and it cannot be refused. Great good fortune.
In a time of giving upward, the fifth line (六五) is the one that receives. Yielding, open at the center and seated as ruler, it is given to from every side. Zhu Xi explains that two tortoise shells make a pair, so one worth ten pairs is a great treasure, offered so freely that it cannot be declined. He ties the reading to virtue: whoever has this openness receives its answer.
Top line, yang (上九)changing line in the shared reading
弗損益之，无咎，貞吉，利有攸往，得臣无家。
Without reducing oneself, one adds to others. No blame. Being correct and firm brings good fortune. It is favorable to have somewhere to go. One gains servants beyond the bounds of a household.
The top line (上九) has received the most and now wants to give back. Zhu Xi notes that someone placed high can benefit others without first reducing himself, a kindness that costs nothing. Hence there is no blame, though correctness is still the condition for good fortune and for going forward. Kindness of that kind reaches far, so the servants it gains are not confined to one household.
If you drew this hexagram
Which text to read depends on how many lines are changing. With none, read the judgment; with one, read that line; with more, follow Zhu Xi's rules in the Yixue qimeng.
Text: Zhu Xi, Yuanben Zhouyi benyi (原本周易本義), Siku Quanshu Wenyuange copy, as transcribed by the Kanseki Repository (KR1a0031), corrected and punctuated by K-magpie. Translation and explanation: written by AI (Claude) from Zhu Xi's commentary and checked against the text and commentary. Sources and the list of corrections are on the Today's Hexagram page.
Characters corrected in this hexagram — image: 窒慾 → 窒欲