Computer Science vs. Software Engineering; although usually the label "Computer Science" is applied to both.

Paraphrasing the PDF:

Loosely speaking, I mean the distinction between programmers who regard their central aim as being to solve problems, and those who are more concerned with building and understanding theories... If you are unsure to which class you belong, then consider the following two statements. (i) The point of solving problems is to understand computation better. (ii) The point of understanding computation is to become better able to solve problems.

Here (i) corresponds to Computer Science and (ii) to Software Engineering.