diff --git a/Concurrent Systems/notes/8 - Enhancing Liveness Properties.md b/Concurrent Systems/notes/8 - Enhancing Liveness Properties.md
index be37e3c..6fb7742 100644
--- a/Concurrent Systems/notes/8 - Enhancing Liveness Properties.md	
+++ b/Concurrent Systems/notes/8 - Enhancing Liveness Properties.md	
@@ -36,7 +36,7 @@ stop_help(i) :=
 *Proof:*
 By contr., $\exists \tau$ s.t. $\exists$ many (> 0) op.'s invoked concurrently that never terminate.
 Let Q be the set of proc.'s that performed these invocations.
-- by enrichment, eventually `NEED_HELP[i]=true` forever ($\forall i\in Q$)
+- by enrichment (def. at the beginning), eventually `NEED_HELP[i]=true` forever ($\forall i\in Q$)
 - since crashes are fail-stop, eventually `NEED_HELP[j]` is no longer modified ($\forall j \not \in Q$)
 	- $\exists \tau' \geq \tau$ where all proc.'s in Q compute the same X