Not Even Wrong

Browsing through the pages of "Conceptual Foundations of Quantum Field Theory" edited by Tian Yu Cao, I see the following (in John Stachel's essay):

Others were less cautious in their approach to quantum gravity. In their first paper on quantum electrodynamics, Heisenberg and Pauli asserted that:

quantization of the gravitational field, which appears to be necessary for physical reasons [in a footnote, they refer to works of Einstein and Klein cited above], may be carried out without any new difficulties by means of a formalism fully analogous to that applied here.

Almost seventy years [1999] have elapsed since this casual prediction, and we are still without a quantum theory of gravity!

Well, strictly, Pauli was wrong, rather than not even wrong.