As Stepanov said: “[Generic] algorithms are defined on algebraic structures”. He even gives an example: “I realized that a parallel reduction algorithm is associated with a semigroup structure type”. If you care about algorithms being maximally reusable (as in “just reuse”, rather than “tweak and reuse”), you definitely want to adopt an abstract-algebraic mindset.

Source: http://www.stlport.org/resources/StepanovUSA.html