Recent decisions have given legal identity to rivers such as Te Awa Tupua in New Zealand, and the Ganges and Yamuna in India, effectively treating them as having all the rights, duties and liabilities of a legal person. Looking at such cases, in which the enduring fiction of the legal person is extended over an increasingly wide range of referents, we are reminded that this fiction is anything but marginal – especially in the law of any jurisdiction influenced, however indirectly, by Roman jurisprudence. This paper begins from the point of view that the anthropological embedding of the juridical person ought not to be anachronistically attributed to the Roman ‘law of persons’ in which its craft originated. Rather, we suggest, the well-known Christian metaphysicalization of the juridical person as a moral entity not only adds to but also transforms and displaces that law as a juristic enterprise. What is marginalized in this sense is in fact Roman law's discrete and self-conscious techniques of shaping the legal person. This chapter aims not just to highlight the familiar fate of the person under the influence of church doctrine, but also to draw a contemporary inspiration – and, more cautiously, a critical potential – from a return to a casuistic, concrete and immanent conception of the jurisprudential art of crafting the person. Rather than argue for the inclusion of excluded identities within law's categories (thus extending such categories but doing nothing to challenge the often heteronormative construction of the identities it encompasses), this chapter asks what would it mean to return to an ‘experimental’ law of persons (or a ‘profaned’ art of fashioning the person, in Giorgio Agamben's sense)? Might this eventually be a path by which to liberate juristic technique to new uses?