\begin{tikzpicture}[>=stealth']
  \matrix[column 1/.style={nodes={text width=8em,text ragged}}] at (-3,-1)
  {
    \node {$\mathsf{allpast}\leq \mathsf{past}$}; \\
    \node {$\mathsf{allpast}\leq \mathsf{pstpart}$}; \\
  };
  \node (ded) at (0,0) {$\mathsf{past}$};
  \node (ened) at (2,0) {$\mathsf{pstpart}$};
  \node (dened) at (1,-2) {$\mathsf{allpast}$};

  \draw[<-] (ded) to (dened);
  \draw[<-] (ened) to (dened);
\end{tikzpicture}

%%% Local Variables:
%%% mode: latex
%%% TeX-master: "../../morphology"
%%% End: