  As a development of our previous work, this paper is concerned with the
Greenberger-Horne-Zeilinger (GHZ) nonlocality for continuous variable cases.
The discussion is based on the introduction of a pseudospin operator, which has
the same algebra as the Pauli operator, for each of the $N$ modes of a light
field. Then the Bell-CHSH (Clauser, Horne, Shimony and Holt) inequality is
presented for the $N$ modes, each of which has a continuous degree of freedom.
Following Mermin's argument, it is demonstrated that for $N$-mode
parity-entangled GHZ states (in an infinite-dimensional Hilbert space) of the
light field, the contradictions between quantum mechanics and local realism
grow exponentially with $N$, similarly to the usual $N$-spin cases.
