doc/concepts.tex: Fix subclass/superclass confusion.

If I can't get this right, my readers don't stand a chance.

diff --git a/doc/concepts.tex b/doc/concepts.tex
index 6b21109..b9aab2f 100644 (file)
--- a/doc/concepts.tex
+++ b/doc/concepts.tex
@@ -313,7 +313,7 @@ qualified by the defining class's nickname.
 \subsubsection{Slot initializers}
 As well as defining slot names and types, a class can also associate an
 \emph{initial value} with each slot defined by itself or one of its
-subclasses.  A class $C$ provides an \emph{initialization message} (see
+superclasses.  A class $C$ provides an \emph{initialization message} (see
 \xref{sec:concepts.lifecycle.birth}, and \xref{sec:structures.root.sodclass})
 whose methods set the slots of a \emph{direct} instance of the class to the
 correct initial values.  If several of $C$'s superclasses define initializers