Gao Zi I · Passage 08 / 20 · 孟子 6A.8
Mencius 6A.8: Niu Mountain and the loss of the good heart
With the image of Niu Mountain stripped by axes day after day, Mencius explains that people do not appear base because they never had goodness.
孟子曰:「牛山之木嘗美矣。以其郊於大國也,斧斤伐之,可以為美乎?是其日夜之所息,雨露之所潤,非無萌蘗之生焉,牛羊又從而牧之,是以若彼濯濯也。人見其濯濯也,以為未嘗有材焉,此豈山之性也哉?雖存乎人者,豈無仁義之心哉?其所以放其良心者,亦猶斧斤之於木也。旦旦而伐之,可以為美乎?其日夜之所息,平旦之氣,其好惡與人相近也者幾希,則其旦晝之所為,有梏亡之矣。梏之反覆,則其夜氣不足以存。夜氣不足以存,則其違禽獸不遠矣。人見其禽獸也,而以為未嘗有才焉者,是豈人之情也哉?故茍得其養,無物不長;茍失其養,無物不消。孔子曰:『操則存,舍則亡。出入無時,莫知其鄉。』惟心之謂與?」
Mencius said, 'The trees of the Niu mountain were once beautiful. Being situated, however, in the borders of a large State, they were hewn down with axes and bills - and could they retain their beauty? Still through the activity of the vegetative life day and night, and the nourishing influence of the rain and dew, they were not without buds and sprouts springing forth, but then came the cattle and goats and browsed upon them. To these things is owing the bare and stripped appearance of the mountain, and when people now see it, they think it was never finely wooded. But is this the nature of the mountain? And so also of what properly belongs to man; shall it be said that the mind of any man was without benevolence and righteousness? The way in which a man loses his proper goodness of mind is like the way in which the trees are denuded by axes and bills. Hewn down day after day, can it - the mind - retain its beauty? But there is a development of its life day and night, and in the calm air of the morning, just between night and day, the mind feels in a degree those desires and aversions which are proper to humanity, but the feeling is not strong, and it is fettered and destroyed by what takes place during the day. This fettering taking place again and again, the restorative influence of the night is not sufficient to preserve the proper goodness of the mind; and when this proves insufficient for that purpose, the nature becomes not much different from that of the irrational animals, and when people now see it, they think that it never had those powers which I assert. But does this condition represent the feelings proper to humanity? Therefore, if it receive its proper nourishment, there is nothing which will not grow. If it lose its proper nourishment, there is nothing which will not decay away. Confucius said, "Hold it fast, and it remains with you. Let it go, and you lose it. Its outgoing and incoming cannot be defined as to time or place." It is the mind of which this is said!'
Priority note
A human-edited reading layer
Central question
Why does Mencius use Niu Mountain to explain the human heart?
Direct answer
Because he wants to correct a common mistake: when people later look coarse, numb, or nearly beast-like, observers assume they never had moral power. Mencius says they are more like a once-lush mountain repeatedly cut bare.
First principle
Much corruption does not come from 'never having had goodness' but from long deprivation of its proper nourishment.
Why it matters
This is one of the most explanatory pages in Mencius on human goodness, serving strong search intent around Niu Mountain, the lost good heart, and moral decline.
Further reading
What this passage is doing
This is passage 8 of 20 in Gao Zi I. The cleanest entry point is "The trees of the Niu mountain were once…". In context, it works as part of Mencius's argument about human goodness, desire, and the debates with Gaozi and can be read alongside Human nature, Humane government / kingly way, Flood-like qi.
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Gao Zi I is the central battleground for human goodness and the arguments with Gaozi.
Related principles
Citation note
Do not turn the metaphor into simple environmental determinism. Mencius also says 'hold it and it remains; let it go and you lose it,' keeping human responsibility in view.