Absolutism about quantifiers, to a first approximation, is the view that there is a universe of quantification—M, say—that contains absolutely everything. Relativism is the opposing view. Some relativists, motivated by concerns relating to “indefinite extensibility”, contend that we can come to quantify over a wider universe, M’, containing objects—such as the “Russell” set of non-self-membered members of M—which demonstrably do not belong to the initial universe, M. This view faces an explanatory challenge: how do universes expand? Just what is going on when—to indulge in the usual metaphor—we “form” the Russell set? This talk tentatively outlines a highly idealised answer to such questions.