Add section numbering to some of the larger subdocuments.
diff --git a/Doc/tutorial/index.rst b/Doc/tutorial/index.rst
index dfc6ac0..8a1a8fb 100644
--- a/Doc/tutorial/index.rst
+++ b/Doc/tutorial/index.rst
@@ -44,6 +44,7 @@
 The :ref:`glossary` is also worth going through.
 
 .. toctree::
+   :numbered:
 
    appetite.rst
    interpreter.rst