diff --git a/lib/git/object.rb b/lib/git/object.rb
index 7a190ea7..826315aa 100644
--- a/lib/git/object.rb
+++ b/lib/git/object.rb
@@ -53,8 +53,9 @@ def grep(string, path_limiter = nil, opts = {})
         @base.lib.grep(string, opts)
       end
       
-      def diff(objectish)
-        Git::Diff.new(@base, @objectish, objectish)
+      def diff(objectish,inverse)
+        return Git::Diff.new(@base, @objectish, objectish) unless inverse
+        Git::Diff.new(@base, objectish, @objectish)
       end
       
       def log(count = 30)
@@ -203,8 +204,8 @@ def committer_date
       end
       alias_method :date, :committer_date
 
-      def diff_parent
-        diff(parent)
+      def diff_parent(inverse=false)
+        diff(parent,inverse)
       end
       
       def set_commit(data)