   #     its 'name', -> should equal('Fred')
   its: (attribute, definition) ->
     it "#{attribute} #{Spec.Util.descriptionize definition}", ->
-      value = @subject[attribute]
-      value = value.call @subject if typeof value is 'function'
-      @subject = value
+      value = @_subject[attribute]
+      value = value.call @_subject if typeof value is 'function'
+      @_subject = value
       definition.call this
 
   # Runs a test against @subject

  #     subject -> new Employee()
  #     it -> shouldNot be(null)
  shouldNot: (matcher) ->
    expect(@subject).notTo matcher

  # Creates a new mock object
  #

  #     subject -> new Employee()
  #     it -> should beAnInstanceOf(Employee)
  should: (matcher) ->
    expect(@_subject).to matcher

  # Runs a negative test against @subject
  #
