If anyone examines the state of affairs outside the Christian fold, he
will easily discover the principle trends that not a few learned men are
following. Some imprudently and indiscreetly hold that evolution, which has not
been fully proved even in the domain of natural sciences, explains the origin of
all things, and audaciously support the monistic and pantheistic opinion that
the world is in continual evolution. Communists gladly subscribe to this opinion
so that, when the souls of men have been deprived of every idea of a personal
God, they may the more efficaciously defend and propagate their dialectical
materialism.
Pope Pius XII, Humani Generis (Click here for full text)
