How can cognitive psychology make a contribution to critical psychologies of science and technology? Here, we read cognitive experimental research on categorization diffractively (Barad, 2007), cutting between the commitment to positivist-empiricist ontology in any given experimental set up, and the empirical conclusions that human categorization practices are inherently hybrid. In so doing, we mean to exemplify the difference made by reading cognitive psychology as either non-critical (on the grounds of its positivist-empiricist ontology) or reparatively (on the basis of its conclusions) as a resource for critical psychology. We aim this intervention to normalize the idea that humans think queerly, and particularly to engage long-standing discussion of the relationship between criticality and positivist-empiricist methods in LGBTQ+ psychology. We aim to exemplify the difference that this diffractive reading can make, by drawing out its relevance for contemporary psychosocial research in intersex studies