diff --git a/core/src/main/java/com/pholser/junit/quickcheck/internal/Reflection.java b/core/src/main/java/com/pholser/junit/quickcheck/internal/Reflection.java
index e0453932e..3228b66ec 100644
--- a/core/src/main/java/com/pholser/junit/quickcheck/internal/Reflection.java
+++ b/core/src/main/java/com/pholser/junit/quickcheck/internal/Reflection.java
@@ -48,7 +48,7 @@ a copy of this software and associated documentation files (the
 import java.util.Arrays;
 import java.util.Collections;
 import java.util.HashMap;
-import java.util.HashSet;
+import java.util.LinkedHashSet;
 import java.util.List;
 import java.util.Map;
 import java.util.Set;
@@ -135,7 +135,7 @@ public static <T> T instantiate(Constructor<T> ctor, Object... args) {
     }
 
     public static Set<Type<?>> supertypes(Type<?> bottom) {
-        Set<Type<?>> supertypes = new HashSet<>();
+        Set<Type<?>> supertypes = new LinkedHashSet<>();
         supertypes.add(bottom);
         supertypes.addAll(bottom.getAllTypesAssignableFromThis());
         return supertypes;