问：「『生之谓性』，告子亦说得是，孟子如何非之？」
先生曰：「固是性，但告子认得一边去了，不晓得头脑；若晓得头脑，如此说亦是。孟子亦曰：『形色，天性也。』这也是指气说。」又曰：「凡人信口说，任意行，皆说此是依我心性出来，此是所谓生之谓性；然却要有过差。若晓得头脑，依吾良知上说出来，行将去，便自是停当。然良知亦只是这口说，这身行，岂能外得气，别有个去行去说。故曰：『论性不论气，不备；论气不论性，不明。』气亦性也，性亦气也，但须认得头脑是当。」
问：「『生之谓性』，告子说得也是，孟子为什么非难他？」
先生说：「固然也是性，但告子只认得一边，不懂得头脑；若懂得头脑，这样说也可以。孟子也说：『形色，天性也。』这也是就气上说的。」又说：「凡人信口说、任意行，都说这是依我的心性出来的，这就是所谓生之谓性；然而会有过差。若懂得头脑，依着良知说出来、做出去，自然停当。然而良知也只是这张口说、这个身行，怎能离得了气，另外有个去说去行的？所以说：『论性不论气，不备；论气不论性，不明。』气也是性，性也是气，只是必须认得头脑妥当。」
Asked: 'Life is what is called nature — Gaozi said aright; why did Mencius condemn him?'
The Master said: 'It is nature indeed; only Gaozi took one side, missing the head. Knowing the head, even that way of speaking will serve. Mencius too said form and color are heavenly nature — that also speaks of breath. Anyone speaking at random and acting at will says it comes from my own heart and nature — that is life-is-nature; yet it runs past the mark. Knowing the head, spoken and done by innate knowledge, it lands right of itself. And innate knowledge too is only this mouth speaking, this body acting — how leave the breath, with another to speak and act? Hence: nature without breath is incomplete; breath without nature unclear. Breath is nature, nature breath — only the head must be rightly held.'