 Barad’s metaphor of “diffraction patterns” is taken from Donna Haraway (see particularly Haraway 1992), who proposed diffraction as an alternative to the metaphor of reflection. While both are optical metaphors, Barad notes that reflection emphasizes sameness and so evokes essentialism—the discovery of what is the same in what is under investigation. Diffraction is about differences and moves the researcher towards tracing the histories of these differences, rather than fitting them into preconceived binaries (Barad 2007: 29–30). Barad describes this process of knowing the material world as “intra-action” rather than interaction. In doing so, she emphasizes that agency is not an attribute—something that someone has—but rather is the involvement in the iterative practices that constitute materiality (Barad 2007: 178). For Barad this intra-action entails the inseparability of science, ontology, epistemology, and ethics and hence the pun on “matter” that runs throughout the new materialism. Our practices matter both in the sense of making a difference and in the sense of being involved in the configuring and reconfiguring of the material world.