It is the same with prophecies, miracles, divination by dreams, sorceries,
etc.

For if there had been nothing true in all this, men would have believed
nothing of them; and thus, instead of concluding that there are no true
miracles because there are so many false, we must, on the contrary, say that
there certainly are true miracles, since there are false, and that there are
false miracles only because some are true. We must reason in the same way
about religion; for it would not be possible that men should have imagined
so many false religions, if there had not been a true one. The objection to
this is that savages have a religion; but the answer is that they have heard
the true spoken of, as appears by the Deluge, circumcision, the cross of
Saint Andrew, etc.

818. Having considered how it comes that there are so many false miracles,
false revelations, sorceries, etc., it has seemed to me that the true cause
is that there are some true; for it would not be possible that there should
be so many false miracles, if there were none true, nor so many false
revelations, if there were none true, nor so many false religions, if there
were not one true. For if there had never been all this, it is almost
impossible that men should have imagined it, and still more impossible that
so many others should have believed it. But as there have been very great
things true, and as