In Matterphorics, Daniela Gandorfer challenges modernist legal theory’s separation of concepts from matter, developing a mode of theory attuned to indeterminacy, relationality, and material entanglement. Gandorfer offers a method for generating legal concepts that respond to ontological complexity rather than reducing the world to fixed categories or representational entities. Through a range of recent case studies ranging from outer space exploration and Red Bull’s high-altitude freefalls to seabed mining, cryonics, and the copyrighting of DNA, she shows how law is unsettled when confronted with technological frontiers and planetary transformations. Instead of treating law as an abstract system, she proposes it as a creative and situated practice—one that must continually reimagine its concepts in response to shifting relations between matter, technology, and thought. In so doing, Gandorfer formulates legal theory as a creative and situated response to planetary and technological transformation.