diff --git a/system theoretic process analysis.md b/system theoretic process analysis.md
index ec05a99bf..49714f596 100644
--- a/system theoretic process analysis.md	
+++ b/system theoretic process analysis.md	
@@ -21,4 +21,6 @@
 		- ![[Pasted image 20210718234132.png]]
 		- a control structure is a system model that is composed of feedback control loops.
 			- a good control structure will enforce the system level constraints.
-		- 
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+		- control goes down, feedback goes up
+			- vertical axis represents a hierarchy ([[heterarchy]]? perhaps in voting systems)
+		- responsibilities can be assigned to each control structure entity; they are refinements of system level constraints
\ No newline at end of file