Dan Yingst

Virtually all errors in thought are the result of a misunderstanding or failure to appreciate the significance of the Incarnation.

Alternatively:  Reality is fundamentally Incarnational, and a failure to recognize this will always lead to error.

Modern thought denies the Incarnation (generally by refusing to admit the union of material and spiritual, giving undue precedence to one or the other) and the reason for the Incarnation (i.e. original sin).