diff --git a/causality.txt b/causality.txt
index cf8a2e2..5987b70 100644
--- a/causality.txt
+++ b/causality.txt
@@ -30,4 +30,6 @@ MULTIPLE ACTORS:
 	- could provide a world-simulating primitive that action validity calls could run
 	
 GAME IDEAS:
-	"I'm thinking of a number"
\ No newline at end of file
+	"I'm thinking of a number"
+	
+	irreversible actions (that you can, of course, reverse)
\ No newline at end of file