 Following Gilbert Ryle’s (1931) influential criticisms of Meinong’s theory of non-existent objects, the theory of descriptions has been taken as a model for avoiding ontological commitment to objects, and so logical constructions in general are often seen as being chiefly used to eliminate purported entities. In fact, that goal is at most peripheral to many constructions. The principal goal of these constructions is to allow the proof of propositions that would otherwise have to be assumed as axioms or hypotheses. Nor need the introduction of constructions always result in the elimination of problematic entities. Yet other constructions should be seen more as reductions of one class of entity to another, or replacements of one notion by a more precise, mathematical, substitute.