diff --git a/lib/mutant/mutator/node/connective/binary.rb b/lib/mutant/mutator/node/connective/binary.rb
index 8b2cbdb1..44b17360 100644
--- a/lib/mutant/mutator/node/connective/binary.rb
+++ b/lib/mutant/mutator/node/connective/binary.rb
@@ -49,7 +49,7 @@ module Mutant
           #
           def mutate_operands
             emit(s(node.type, n_not(left), right))
-            emit(s(node.type, left, n_not(right)))
+            emit(n_not(node))
           end
 
         end # Binary
diff --git a/spec/unit/mutant/mutator/node/connective/binary/mutation_spec.rb b/spec/unit/mutant/mutator/node/connective/binary/mutation_spec.rb
index 2d39469e..a51012d1 100644
--- a/spec/unit/mutant/mutator/node/connective/binary/mutation_spec.rb
+++ b/spec/unit/mutant/mutator/node/connective/binary/mutation_spec.rb
@@ -13,7 +13,7 @@ describe Mutant::Mutator::Node::Connective::Binary, 'mutations' do
       mutations << 'true or false'
 
       mutations << 'not true and false'
-      mutations << 'true and not false'
+      mutations << 'not(true and false)'
     end
 
     it_should_behave_like 'a mutator'
@@ -31,7 +31,7 @@ describe Mutant::Mutator::Node::Connective::Binary, 'mutations' do
       mutations << 'true and false'
 
       mutations << 'not true or false'
-      mutations << 'true or not false'
+      mutations << 'not(true or false)'
     end
 
     it_should_behave_like 'a mutator'