diff --git a/lib/compare/dynamic.js b/lib/compare/dynamic.js
index 35d6a96..98a115f 100644
--- a/lib/compare/dynamic.js
+++ b/lib/compare/dynamic.js
@@ -13,7 +13,10 @@ export const compareDynamic = x => y =>
   compareTypes(getType(x))(getType(y))
     || makeCompareFn(getType(x))(getInst(x))(getInst(y));
 
-const cannotCompareTypeVarInstances = _ => _ => { throw new Error("Cannot compare instance of type variables"); }
+// const cannotCompareTypeVarInstances = _ => _ => { throw new Error("Cannot compare instance of type variables"); }
+
+
+const cannotCompareTypeVarInstances = _ => _ => 0;
 
 const typeSymbolToCmp = new Map([
   [symbolInt     , compareInts     ],