👉 In mathematics, a non-infinite set is one in which every element has a successor. This means that if you have an infinite set A, there exists at least one natural number n such that for all elements x in A, x + 1 also belongs to A. For example, the set {1, 2, 3} is non-infinite because any element greater than or equal to 1 has a successor (2) and any element less than or equal to 3