You can see that Mike has something in his hand. Wait, that’s my arm! He must want something. Dad didn’t understand what it was, so I guess Mike wants to use my arm to help accomplish his goal.
Autism has degrees of severity. That is the reason for defining that condition as Autism Spectrum Disorder (ASD). My understanding, borne out by observations and interactions with my brother, is that those on the lower end of the spectrum do not understand that other minds exist. Autistic aloneness seems to be characterized by the idea that the autistic person is the only consciousness in his or her universe. Everything else is inanimate.
If one does not realize immediately that the object in Mike’s hand is my arm, for an instant we see the world from Mike’s perspective.