You're implicitly assuming that you yourself have free will and/or are too complicated for a computer to mimic. Because if not, then I could just be a computer which doesn't even hear the words you are saying, and is merely reacting to the words I would hear if I did have ears (which I can do because I have your entire sourcecode built into me).

The longer you meditate upon this very silly paradox, the more unsettling it becomes :)