 It is instructive to compare how the medical and social models would address these challenges. The medical model suggests a disability identity that is both fragmented and negative. Because the medical model defines disability in terms of particular physical or mental impairments, the primary commonalities it recognizes among disabled people are strictly functional; it views the blind person and the deaf person as having very different problems. Although it could recognize the fact that such biomedically distinct conditions had similar social consequences—stigmatization and exclusion—it would treat those similar consequences merely as secondary effects of the two conditions. Even within a single impairment, a medical model encourages distinctions based on etiology. For example, it would distinguish blindness due to Leber’s congenital amaurosis from blindness due to retinaopathy of prematurity, focusing on genetic testing for the former and treatment for the latter, and placing less emphasis on the shared challenges of living with blindness. Although this narrow focus may be appropriate for the purposes of clinical intervention, it obscures the recognition of disability as a social and political problem, except insofar as it raises perennial questions about how to distribute scarce health-care resources (Barnartt et al. 2001).