Vagrant predicates are logical constructions that exhibit an inherent limit to conceptual knowledge.
[1] Such predicates can be used in general descriptions but are self-contradictory when applied to particulars.
Vagrant predicates have been proposed and studied by Nicholas Rescher.
[2] When infinity is thought of as a number greater than any given, a similar idea is conceived.
Rescher has used vagrant predicates to solve the vagueness problem.