We wear the mask that grins and lies,
It hides our cheeks and shades our eyes,—
This debt we pay to human guile;
With torn and bleeding hearts we smile,
And mouth with myriad subtleties.
Why should the world be over-wise
The connotation invoked by  “this debt”  suggests that something is owed. But the sentence quickly turns out to refer to the sacrifice that must be made in order to be cunning and duplicitous. 
 This poem has traditionally been interpreted as an expression of black experience. Some scholars have seen it as primarily about racial relations, the dynamics of which can be extended to other systems of oppression. But in this line, the word  “human”  opens up exegetical possibilities in a much more universal way.
We Wear the Mask