The diagnosis and perception of autism have undergone significant transformations throughout history. Initially conceptualised as a symptom of schizophrenia, autism later emerged as a distinct diagnosis, evolving into the broader classification of autism spectrum disorder (ASD). This essay explores the main shifts in the understanding of autism throughout its history and different approaches to its treatment. While the traditional psychiatric perspective aligns with a naturalist view of disease, the Neurodiversity Movement advocates for a normative approach, emphasising societal adaptation over medical intervention. The study examines historical milestones, including the contributions of Eugen Bleuler, Grunya Sukhareva, Leo Kanner, and Hans Asperger, alongside the conceptual transition from low- and high-functioning autism to the spectrum model. It also discusses the implications of language in shaping autism discourse, highlighting the shift from person-first to identity-first terminology. The essay ultimately argues that the expansion of the autism diagnosis supports the neurodiversity paradigm, which fosters greater inclusion and empowerment of neurodivergent individuals. However, considerations of severity and linguistic framing remain crucial in advancing this perspective.