JESS: fired in wrong order!

[S�bastien Darveau]

Why does the last rule is fired but not the first one (rule-1 will fire if I remove rule-2) ?   (assert (f1 4 6 1 4 1 nil)) (assert (f2 -7 0 4 9))   (deffunction same-name (?n1 ?n2)  (if (eq (mod ?n1 7) (mod ?n2 7)) then      true   else      false))   (defrule rule-1  (f1 ?n1 ?n2 ?n3 ? ? ?)  (f2 ?bc ?tc ?ac&:(same-name ?ac ?n1)|:(same-name ?ac ?n2)|:(same-name ?ac ?n3) ?sc)  =>  (assert (something)))   (defrule rule-2  (f1 ?n1 ?n2 ?n3 ? ? ?)  (f2 ?bc ?ac&:(same-name ?ac ?n1)|:(same-name ?ac ?n2)|:(same-name ?ac ?n3) ?ac ?sc)  =>  (assert (something)))   Thank you.