diff -r f1743ce9dbf1 -r 2656354c7544 ProgTutorial/Advanced.thy
--- a/ProgTutorial/Advanced.thy	Wed Dec 02 17:08:37 2009 +0100
+++ b/ProgTutorial/Advanced.thy	Thu Dec 03 14:19:13 2009 +0100
@@ -14,6 +14,12 @@
 chapter {* Advanced Isabelle *}
 
 text {*
+   \begin{flushright}
+  {\em All things are difficult before they are easy.} \\[1ex]
+  proverb
+  \end{flushright}
+
+  \medskip
   While terms, types and theorems are the most basic data structures in
   Isabelle, there are a number of layers built on top of them. Most of these
   layers are concerned with storing and manipulating data. Handling them