Mathematics as the study of “relationships” rather than “patterns” but they are obviously closely related(!). There is a field of mathematics called “category theory” that is just about as abstract as you can get (the textbook, in the preface, said category theory is often called “abstract nonsense” with no sense of that being derogatory at all).
A category has “objects” and “relations”. The collection of all sets is a category with sets as objects and functions between them as “relations”. The collection of topological spaces is a category with the topological spaces being the objects and continuous functions from one topological space to another being the relations.