Convert "Types, types, types" slide into "How to think haskell?"

This should give a general idea of how to think haskell.

VL1.tex

@@ -242,13 +242,23 @@ Let's reiterate. Haskell is:
 \end{frame}
 
 \begin{frame}
-\frametitle{Types, types, types}
-\begin{itemize}
+\frametitle{How to think haskell?}
+\begin{itemize}[<+->]
 \item think in types!
+\begin{itemize}[<+->]
 \item don't be afraid of type errors
 \item let the type-checker do the work for you (does this function do what I think it does?)
 \item understand functions just by looking at their type signature?
 \end{itemize}
+\item think abstract!
+\begin{itemize}[<+->]
+\item don't repeat yourself!
+\item "develop a solution space, rather than an individual solution" -- Ralf Hinze
+\item "imagine a graph, rather than a single path" -- Ralf Hinze
+\item "first solve a more general problem, then extract the interesting bits and pieces by transforming the general program into more specialised ones" -- Ralf Hinze
+\end{itemize}
+\item solve atomic parts of general problems and combine them into greater solution
+\end{itemize}
 \end{frame}
 
 \begin{frame}[fragile]