"In New Spain Christian fanaticism immediately destroyed whatever of arts and civilization existed among the natives, and that this was not inconsiderable is shown by the numerous monuments now in ruins which place beyond a doubt the former existence of a tolerably high degree of culture. But in the place of this not a trace of Christian civilization is now to be observed among the existing Indians, and the resident Catholic clergy keep the Indians purposely in a state of the greatest ignorance and stupidity (see Richthofen, Die Zustande der Republic Mexico, Berlin, 1854).
"Thus Christianity has always acted consistently in accordance with the principles of one of the fathers of the Church, Tertullian, who says: '_Desire of knowledge is no longer necessary since Jesus Christ, nor is investigation necessary since the Gospel._' If the civilization of the European and especially of Christian Nations has notwithstanding made such enormous progress in the course of centuries, an unprejudiced consideration of history can only tell us that this has taken place not by means of Christianity, but in spite of it. And this is a sufficient indication to what an extent this civilization must still be capable of development when once it shall be completely freed from the narrow bounds of old superstitious and religious embarrassments!"
"We must therefore endeavor to form convictions which are not to stand once and for all, as philosophers and theologians usually do, but such as may change and become improved with the advance of knowledge. Whoever does not recognize this and gives himself up once for all to a belief which he regards as final truth, whether it be of a theological or philosophical kind, is of course incapable of accepting a conviction supported upon scientific grounds. Unfortunately our whole education is founded upon an early systematic curbing and fettering of the intellect in the direction of dogmatic (philosophical or theological) doctrines of faith, and only a comparatively small number of strong minds succeed in after years in freeing themselves by their own powers from these fetters, whilst the majority remain captive in the accustomed bonds and form their judgment in accordance with the celebrated saying of Bishop Berkeley: 'Few men think; but all will have opinions.'"--Buchner, "Man in the Past, Present, and Future."