Many universities claim that there are three general areas in mathematics: analysis, which deals with continuous aspects of mathematics; algebra, which deals with discrete aspects; and geometry.
If you were to chose the fourth, what would it be?
Many universities claim that there are three general areas in mathematics: analysis, which deals with continuous aspects of mathematics; algebra, which deals with discrete aspects; and geometry.
If you were to chose the fourth, what would it be?
Wikipedia lists four ideas on which pure mathematics focuses:
Quantity
Structure
Space
Change
The second, third, and fourth categories seem to match your labels of algebra, geometry, and analysis, respectively. The first could probably be labeled number theory, but Wikipedia also lists number theory as studying structure (so perhaps "quantity" shouldn't really be a separate category?). If the quantity category were to be kept, it could correspond to arithmetic. However, it seems demeaning to analysis/geometry/algebra to elevate arithmetic to a "pillar of mathematics".
Since this is quite a subjective question, the words of whoever wrote that section of the article are not fact. Neither are my opinions particularly supported by ethos.