diff --git a/preserves.md b/preserves.md
index 24ea42a..ceb6651 100644
--- a/preserves.md
+++ b/preserves.md
@@ -39,7 +39,7 @@ definition of the *values* that we want to work with and give them
 meaning independent of their syntax.
 
 Our `Value`s fall into two broad categories: *atomic* and *compound*
-data.
+data. Every `Value` is finite and non-cyclic.
 
                           Value = Atom
                                 | Compound