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From Deluge:
III. UNIVERSALITY OF THE DELUGE
The Biblical account ascribes some kind of a universality to the
Flood. But it may have been geographically universal, or it may have
been only anthropologically universal. In other words, the Flood may
have covered the whole earth, or it may have destroyed all men,
covering only a certain part of the earth. Till about the seventeenth
century, it was generally believed that the Deluge had been
geographically universal, and this opinion is defended even in our
days by some conservative scholars (cf. Kaulen in Kirchenlexikon). But
two hundred years of theological and scientific study devoted to the
question have thrown so much light on it that we may now defend the
following conclusions:
(1) The geographical universality of the Deluge may be safely
abandoned.
Neither Sacred Scripture nor universal ecclesiastical tradition, nor
again scientific considerations, render it advisable to adhere to the
opinion that the Flood covered the whole surface of the earth.