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diff --git a/topics/_week6_plexy.mdwn b/topics/_week6_plexy.mdwn
index caf3e69d..79d081e3 100644
--- a/topics/_week6_plexy.mdwn
+++ b/topics/_week6_plexy.mdwn
@@ -1,5 +1,5 @@
-Motivating types; motivating the Maybe monad
-============================================
+Motivating types; our first glimpse of the Maybe monad
+======================================================
 
 In [[a long footnote discussing Russell|readings/kaplan-plexy.pdf]],
 Kaplan 1989:496 poses a problem for the interaction of structured
@@ -47,8 +47,10 @@ meaning.
 more complicated expression that, he argues, refers to Plexy, but this
 nicety is not crucial to our discussion here.)
 
+## Types to the rescue
+
 Kaplan's solution is, in effect, to impose a type system on his
-grammar in such a way that structured meanings cannot be confused with
+grammar in such a way that complex structured meanings cannot be confused with
 the referent of a directly-referential term.  He suggests that the
 meaning of a directly referential term always be marked by a special
 bit of structure that is unique to direct reference.  More concretely,
@@ -65,6 +67,8 @@ class of objects that a directly referential term can refer to, and
 the class of objects that can serve as the complex structure
 corresponding to a DP that is not directly referential.
 
+## Motivating Maybe
+
 Kaplan goes on to use this solution to attack a different problem, the
 problem of non-referring names.  Russell supposed that if a name had
 no referent (e.g., *Santa*), a sentence containing that name would
@@ -88,8 +92,8 @@ directly-referential expressions:
     {}   if there is no object that E refers to, or else
     {P}  if E refers to P
 
-In later weeks, we will call this technique the Maybe monad.
+In later weeks, we will call the general form of this technique the Maybe type, and the general strategy for deploying this type the Maybe monad.
 
 
-Kaplan, D. 1989. "Demonstratives. InJ. Almog, J. Perry, & H. Wettstein
+Kaplan, D. 1989. "Demonstratives. In J. Almog, J. Perry, & H. Wettstein
 (Eds.), Themes from Kaplan (pp. 481-563)."