diff --git a/rules/source/rules.pdb b/rules/source/rules.pdb
index d170af3f9a25c87f90897e81a70211c97114866b..c9c10c6012dc03a975dadf382d1961dc2c81d8ec 100644
--- a/rules/source/rules.pdb
+++ b/rules/source/rules.pdb
@@ -40,29 +40,22 @@ rat(g, mg, 1000).
 rat(g, kg, 0.001).
 
 ratio(X, Y, Ratio) :-
-  write("simple ratio "), write(X), write(" "), write(Y), nl,
   rat(X, Y, Ratio).
 ratio(X, Y, Ratio) :-
-  write("reverse ratio "), write(X), write(" "), write(Y), nl,
   rat(Y, X, Z), !, Ratio = 1/Z.
 ratio(X, Y, Ratio) :-
-  write("complex ratio 1 "), write(X), write(" "), write(Y), nl,
   X \== Y,
   rat(Step, _, _),
   Step \== X,
   Step \== Y,
-  write("    trying step "), write(Step), nl,
   ratio(X, Step, R1),
   ratio(Step, Y, R2),
   Ratio = R1 * R2.
 ratio(X, Y, Ratio) :-
-  write("complex ratio 2 "), write(X), write(" "), write(Y), nl,
   X \== Y,
   rat(_, Step, _),
   Step \== X,
   Step \== Y,
-  write("    trying step "), write(Step), nl,
-  write("    trying step "), write(Step), nl,
   ratio(X, Step, R1),
   ratio(Step, Y, R2),
   Ratio = R1 * R2.