diff --git a/scribblings/networks.scrbl b/scribblings/networks.scrbl
index 5945e32..1a73157 100644
--- a/scribblings/networks.scrbl
+++ b/scribblings/networks.scrbl
@@ -335,15 +335,16 @@ Build a Boolean network from a given mapping assigning forms to variables.
 This section provides inference of both unsigned and signed interaction graphs.
 Since the inference of signed interaction graphs is based on analysing the
 dynamics of the networks, it may be quite resource-consuming, especially since
-I allow any syntactic forms in the definitions of the functions.
+any syntactic forms are allowed in the definitions of the functions.
 
-Note the fine difference between @emph{syntactic} interaction graphs and
-interaction graphs generated from the dynamics of the network.
-Syntactic interaction graphs are based on the whether a variable appears or not
-in the form of the function for another variable.  On the other hand, the
-normal, conventional interaction graph records the fact that one variable has
-an impact on the dynamics of the other variable.  Depending on the model, these
-may or may not be the same.
+We use the term @emph{syntactic interaction graph} to refer to the graph in
+which the presence of an arc from @tt{x} to @tt{y} is based on whether @tt{x}
+appears in the form of @tt{y}.  This is quite different from the canonical
+definition of the @emph{interaction graph}, in which the arc from @tt{x} to
+@tt{y} represents the fact that a change in the value of @tt{x} may lead to
+a change in the value of @tt{y}.  Thus the syntactic interaction graph may have
+extra arcs if @tt{x} appears in the form of @tt{y}, but has no actual influence
+on @tt{y}.
 
 @section{Dynamics of networks}