“The facts of life do not penetrate to the sphere in which our beliefs are cherished; they did not engender those beliefs, and they are powerless to destroy them; they can inflict on them continual blows of contradiction and disproof without weakening them; and an avalanche of miseries and maladies succeeding one another without interruption in the bosom of a family will not make it lose faith in either the clemency of its God or the capacity of its physician.”