What are some signs that someone is not autistic?

There is no single checklist that proves someone is not autistic, because autism spectrum disorder is diagnosed based on a pattern of developmental history and current traits, and many human behaviors overlap. However, some general indicators that suggest typical social communication development include consistently and intuitively understanding nonverbal cues, easily engaging in back-and-forth conversation across contexts without needing to consciously script responses, flexibly adapting to changes in plans without significant distress, sharing interests in a reciprocal way and showing spontaneous interest in others' perspectives, developing varied pretend play in childhood without strong preference for repetition alone, and not experiencing persistent sensory sensitivities that interfere with daily life. It is important to note that many non-autistic people can be introverted, like routines, or have intense interests, and many autistic people can have strong social skills, especially if they have learned to mask. Absence of one trait does not rule autism in or out. Diagnosis requires comprehensive evaluation of early development, communication, social interaction, and repetitive or sensory patterns by a qualified professional, so assumptions based on stereotypes should be avoided.