Full Idea
A possible axiom is the Large Cardinal Axiom, which asserts that there are more and more stages in the cumulative hierarchy. Infinity can be seen as the first of these stages, and Replacement pushes further in this direction.
Gist of Idea
A Large Cardinal Axiom would assert ever-increasing stages in the hierarchy
Source
Penelope Maddy (Naturalism in Mathematics [1997], I.5)
Book Reference
Maddy,Penelope: 'Naturalism in Mathematics' [OUP 2000], p.73