Mathematical proofs are often evaluated as individuated entities, represented by a printed text, a lecture, a diagram, or some other single presentation. I question this assumption by showing that the identity of a proof is context-dependent and frequently underdetermined by mathematical content alone. Historical cases such as “Cauchy’s” proof of Euler’s polyhedron formula, and Hilbert’s hotel, as well as elementary and advanced contemporary case studies, show that proof identity may shift according to context. Rather than proposing universal criteria of individuation, I present a structuralist-semiotic account in which a proof is understood as a fuzzy network of textual and performative proof-presentations related by partial translations. On this view, properties such as rigor and explanatory value are not intrinsic properties of a single presentation, but emerge from the choice of a relevant corpus and from the interpretation of relations among its members. Historical practices in Arabic geometry, Chinese mathematical commentaries, and Sanskrit mathematics further show that proofs need not be conceived as single arguments from premises to conclusion. Treating proofs as relational and intrinsically plural provides a framework for evaluating mathematical proofs that is more faithful to mathematical practice, to the history of mathematics, and to the interpretive work increasingly foregrounded by formalization and proof assistants.