diff --git a/1FundamentalGroup/Quest0Solutions.agda b/1FundamentalGroup/Quest0Solutions.agda
index 5415de5..6ac2880 100644
--- a/1FundamentalGroup/Quest0Solutions.agda
+++ b/1FundamentalGroup/Quest0Solutions.agda
@@ -43,7 +43,7 @@ pathEmpty : (A : Type) → Type₁
 pathEmpty A = A ≡ ⊥
 
 isoEmpty : (A : Type) → Type
-isoEmpty A = A ≅ ⊥
+isoEmpty A = {!!}
 
 outOf⊥ : (A : Type) → ⊥ → A
 outOf⊥ A ()