If it were not so common a failing to ignore the lessons of the past, it might have been hoped that a certain modesty, of which the necessity is taught us by centuries of error, would have saved a multitude of writers from rushing into premature and denunciative rejection of results which they have not studied, and of which they are incapable to judge. St. Jerome complained that in his day there was no old woman so fatuous as not to assume the right to lay down the law about Scriptural interpretation. It is just the same in these days. Half-taught dogmatists--ἀυτοσχέδιοι δογματισταὶ, as they have been called--may sweepingly condemn the lifelong researches of men far superior to themselves, not only in learning, but in love of truth; they may attribute their conclusions to faithless infatuation, and even to moral obliquity. This has been done over and over again in our own lifetime; and yet such self-constituted and unauthorised defenders of their own prejudices and traditions--which they always identify with the Catholic faith--are impotent to prevent, impotent even greatly to retard, the spread of real knowledge. Many of the now-accepted certainties of science were repudiated a generation ago as absurd and blasphemous. As long as it was possible to put them down by persecution, the thumbscrew and the stake were freely used by priests and inquisitors for their suppression. _E pur si muove._ Theologians who mingled the gold of Revelation with the clay of their own opinions have been driven to correct their past errors. Untaught by experience, religious prejudice is ever heaping up fresh obstacles to oppose the progress of new truths. The obstacles will be swept away in the future as surely as they have been in the past. The eagle, it has been said, which soars through the air does not worry itself how to cross the rivers.