On functional freedom and Penrose's critiques of string theory

In his The Road to Reality as well as in his Fashion, Faith and Fantasy, Roger Penrose criticises string theory and its practitioners from a variety of angles ranging from conceptual, technical, and methodological objections to sociological observations about the string theoretic scientific community. In this article, we assess Penrose's conceptual/technical objections to string theory, focussing in particular upon those which invoke the notion of `functional freedom'. In general, we do not find these arguments to be successful.