As the _summum bonum_ of salvation prescribed the topics of ultimate intellectual interest for the Middle Ages, so the stress which it laid upon one topic rather than another tended to direct their ordering or classification, as well as the proportion of attention devoted to each one. Likewise the form or method of presentation was controlled by the authority of the Scriptural statement of the way and means of salvation, and the well-nigh equally authoritative interpretation of the same by the beatified Fathers. Thus the nature of the _summum bonum_ and the character of its Scriptural statement and patristic exposition suggested the arrangement of topics, and set the method of their treatment in those works of the twelfth and thirteenth centuries which afford the most important presentations of the ultimate intellectual interests of that time. Obvious examples will be Abaelard’s _Sic et non_ and his _Theologia_, Hugo of St. Victor’s _De sacramentis_, the Lombard’s _Books of Sentences_, and the _Summa theologiae_ of Thomas Aquinas. It will be seen in the next chapter that the arrangement of topics in these comprehensive treatises differed from what would have been evolved through the requirements of a systematic presentation of human knowledge. Aquinas sets forth the reasons why one mode of treatment is suitable to philosophy and another to sacred science, and why the latter may omit matters proper for the former, or treat them from another point of view. The supremacy of sacred science is incidentally shown by the argument. In his _Contra Gentiles_[420] chapter four, book second, bears the title: “Quod aliter considerat de creaturis Philosophus et aliter Theologus” (“That the philosopher views the creation in one way and the theologian in another”). In the text he says: