Comment by analog31

It's interesting to see different perspectives on this.

For me, calculus was the first math I learned, where symbols represented something other than pure numbers or tangible points on a plane, and we proved things about higher level abstractions. Of course many of the topics had tangible applications, but it was a launching point towards further abstraction in the higher level math courses.

A friend of mine in grad school was a student in medieval church history, but was assigned to teach a freshman course in modern history. For one class session, he asked a math teacher to give a guest lecture on calculus. Then he lectured on its impact on society.

It's true that most people, including managers and engineers, forget their school math not long after school. Their software tools, such as Excel and CAD, can do the math that they need. One can hope without proof that a little bit of mathematical thinking rubbed off on them.