The german abbess Hildegarde de Bingen († 1179 ) undertook to list the Creation in her Liber subtilitatum diversarum naturarum creaturarum also called Physica, which can be counted among the natural encyclopedies of the Middle Ages. But Hildegarde does not follow the rules of the encyclopaedic genre, by the position which she adopts and claims with regard to the sources of her writings. Visionary, she wants to be independent from any human knowledge, asserts that all she writes comes from God, and thus quotes none of her predecessors. Now, if genius and personal observation certainly have their part in her Physica, only readings can explain some of her information. This paper goes back to the still open question of the sources of Hildegar's...