 Barnes focuses on the category of physical disability and argues that the conditions fitting under the category are “strikingly heterogenous” (2016: 9 and 46) and that there is no feature common to the bodies of all (physically) disabled persons that makes them disabled. On her account, disability is a socially-constructed category that “people have found useful when organizing themselves in a civil rights struggle” and “disability just is whatever the disability rights movement is promoting justice for” (43 – emphasis in original). Barnes adds that the movement’s judgments about which persons and conditions are included under its umbrella are not arbitrary but rather “rule-based” and implicitly treat the category of disability as a “cluster-concept” to be applied to physical conditions that have “some sufficient number of features such as: being subject to social stigma and prejudice; being viewed as unusual or atypical; making ordinary daily tasks difficult or complicated; causing chronic pain; causing barriers to access public places, … requiring the use of mobility aids or assistive technology [and] requiring medical care” (45). What unifies the various conditions categorized as disabilities, in Barnes’s view, is that they “are the kind of thing that the disability rights movement is trying to make the world a better place to live with” (48 – emphasis in original). To be clear, her view is not that the movement is recognizing a “kind of thing” that would exist even in its absence but that the movement creates the kind of thing we call “disability.” Accordingly, if we ask about each of the conditions that fit under the category of physical disability, ‘What does it have common with the other conditions in the category?, then Barnes thinks that the most illuminating answer is that the disability rights movement is fighting for the just treatment of persons with that condition.