  We discuss recent papers by Hartle, Hawking and Hertog, which proposed that
quantum cosmology could predict an inflating universe in models with negative
scalar potentials. Here we show that this is a result of an underlying symmetry
which is manifest in both classical and quantum theory. Moreover, we show that
inflating solutions in such models generally develop tachyonic and ghost
instabilities and are therefore unphysical in realistic theories.
