diff --git a/jedi/cache.py b/jedi/cache.py
index 831b8e50..81d82375 100644
--- a/jedi/cache.py
+++ b/jedi/cache.py
@@ -80,13 +80,13 @@ def time_cache(time_add_setting):
 def memoize_method(method):
     """A normal memoize function."""
     def wrapper(self, *args, **kwargs):
-        dct = self.__dict__.setdefault('_memoize_method_dct', {})
+        cache_dict = self.__dict__.setdefault('_memoize_method_dct', {})
+        dct = cache_dict.setdefault(method, {})
         key = (args, frozenset(kwargs.items()))
         try:
             return dct[key]
         except KeyError:
             result = method(self, *args, **kwargs)
-            # TODO THIS IS FUNDAMENTALLY WRONG, METHOD SHOULD BE INCLUDED.
             dct[key] = result
             return result
     return wrapper