In the section "Christianity and Liberal Arts", there is a distinction between logic and logistic defined by Christianity. "'Logistic is the theory which deals with numerable objects and not with numbers. It does not consider number in the proper sense of the term...' but rather the counting of flocks, addition, subtraction, multiplication and division, always dealing with sensible objects." This definition is very much the same as "useful math" defined by modern day people who question the education of mathematics beyond those mentioned operations. It is interesting to see how some people retain the same view of mathematics when this field has drastically changed and improved our life for hundreds of years.
In correspondence with the above definition: "as for the quadrivium, as the science are called, since they have little to attract in themselves and produce only a meager profit, most of the students neglect them or else omit them entirely". Thanks to the development of technologies, mathematics nowadays is required more and more by other disciplines, rather than being a stand-alone subject. While there is still perceptions of math being "useless" once you graduate from college, this mindset is being altered gradually.
Lastly, I really like what Augustine said about mathematics, where "the principles of logic as the inviolable foundations of knowledge ... Side by side with the logic we find the truths of mathematics .. all there truths are necessarily and unconditionally true; they cannot be contested." I am surprised that at A.D. 386, someone already had such confidence in the nature of mathematics, when there was no computer or any efficient ways to communicate with the rest of the world. The fact that some mathematics can be proven true for thousands of years (and stay true for possible eternity) fascinates me a lot. I really like the feeling of proving something to be true with 100% confidence, and I hope my future students could feel the same satisfaction when they are also able to do so with mathematics.