diff --git a/src/core/Numeric.pm b/src/core/Numeric.pm
index 9425bcbd8f3..12f46e615dc 100644
--- a/src/core/Numeric.pm
+++ b/src/core/Numeric.pm
@@ -3,6 +3,14 @@ role Numeric {
         self;
     }
 
+    method succ(Numeric $x:) {
+        $x + 1;
+    }
+
+    method pred(Numeric $x:) {
+        $x - 1;
+    }
+
     method abs(Numeric $x:) {
         note "$.WHAT() needs a version of .abs";
         fail "$.WHAT() needs a version of .abs";
diff --git a/src/core/Rat.pm b/src/core/Rat.pm
index 27daca35268..8bdf30edb6d 100644
--- a/src/core/Rat.pm
+++ b/src/core/Rat.pm
@@ -54,10 +54,11 @@ class Rat is Cool does Real {
 
     multi method nude() { $.numerator, $.denominator; }
 
-    multi method succ {
+    method succ {
         Rat.new($!numerator + $!denominator, $!denominator);
     }
-    multi method pred {
+
+    method pred {
         Rat.new($!numerator - $!denominator, $!denominator);
     }
 }