diff --git a/lib/liquid/standardfilters.rb b/lib/liquid/standardfilters.rb
index 6ff4f35c..65b51508 100644
--- a/lib/liquid/standardfilters.rb
+++ b/lib/liquid/standardfilters.rb
@@ -422,7 +422,7 @@ module Liquid
     end
 
     def default(input, default_value = '', allow_false: false)
-      if (allow_false ? input.nil? : !input) || input.respond_to?(:empty?) && input.empty?
+      if (allow_false ? input.nil? : !input) || (input.respond_to?(:empty?) && input.empty?)
         default_value
       else
         input