In Hroswitha's time, as in our own, there were people who were strongly opposed to the higher education of women. There were others who would deny them even the elements of an education--who declared that they should be taught anything rather than reading and writing, which were a cause of temptation and sin--that their knowledge should be confined solely to the duties of an ordinary housewife, that their books should consist solely of thimble, thread and needles--"_Et leurs livres, un de, du fil et des aguilles._" Some, it is true, were willing to make an exception in favor of nuns; but, as to all others, the less they knew the better it was for their spiritual, if not for their temporal, welfare also.[41] To those who were thus minded, Hroswitha pithily replied that it was not knowledge itself but the bad use of it that was dangerous--"_Nec scientia scibilis Deum offendit, sed injustitia scientis._" Among other women who were Hroswitha's equals in knowledge, if not in literary attainments, were several other nuns who illumined the closing centuries of the Middle Ages. Chief among these were St. Hildegard, "the sybil of the Rhine"; Herrad, the noted author of the _Hortus Deliciarum--Garden of Delights_--and Matilda and Gertrude, those remarkable mystical writers, whose descriptions of heaven and hell so closely resemble those in the _Divina Commedia_ that many writers are of the opinion that the great Florentine poet must have been familiar with the accounts which they gave of their visions. St. Hildegard was for a third of a century the abbess of the convent of St. Rupert at Bingen. So great was her reputation for sanctity and for the extent and variety of her attainments that she was called "the marvel of Germany." She is without doubt one of the most beautiful and imposing as well as one of the greatest figures of the Middle Ages--great beside such eminent contemporaries as Abelard, Martin of Tours and Bernard of Clairvaux. People from all parts of the Christian world sought her counsel; and her convent at Bingen became a Mecca for all classes and conditions of men and women. But nothing shows better the immense influence which she wielded than her letters of which nearly three hundred have been preserved.