The whole world’s at sixes and sevens, and why the house hasn’t fallen down about our ears long ago is a miracle to me.

Wilder’s line uses the idiom “at sixes and sevens” to convey a world in disorder—socially, morally, or practically—while the image of “the house” not yet collapsing suggests a fragile structure (society, a family, an institution, even existence itself) held together by something other than rational planning. The speaker’s amazement—calling continued stability “a miracle”—captures a recurring Wilder theme: ordinary life persists despite chaos, and the fact that it does can feel providential or inexplicable. The sentence balances cynicism (everything is a mess) with wonder (yet it stands), implying that endurance may be as mysterious as breakdown.