  The Ollivier-Poulin-Zurek definition of objectivity provides a philosophical
basis for the environment as witness formulation of decoherence theory and
hence for quantum Darwinism. It is shown that no account of the reference of
the key terms in this definition can be given that does not render the
definition either empty or circular. It is argued that this is not the fault of
the language used, but of the assumption that the laws of physics are
independent of Hilbert-space decomposition. All evidence suggests that this
latter assumption is true. If it is, decoherence cannot explain the emergence
of classicality.
