diff --git a/Library/Homebrew/cmd/cat.rb b/Library/Homebrew/cmd/cat.rb
index f42fbc0377..b42e54a57a 100644
--- a/Library/Homebrew/cmd/cat.rb
+++ b/Library/Homebrew/cmd/cat.rb
@@ -3,9 +3,11 @@ module Homebrew
     # do not "fix" this to support multiple arguments, the output would be
     # unparsable, if the user wants to cat multiple formula they can call
     # brew cat multiple times.
+    formulae = ARGV.formulae
+    raise FormulaUnspecifiedError if formulae.empty?
+    raise "`brew cat` doesn't support multiple arguments" if formulae.size > 1
 
-    raise FormulaUnspecifiedError if ARGV.named.empty?
     cd HOMEBREW_REPOSITORY
-    exec "cat", ARGV.formulae.first.path, *ARGV.options_only
+    exec "cat", formulae.first.path, *ARGV.options_only
   end
 end