An alien identity is not something easily maintained without means of returning to the state from which that identity originally sprang. It gets diluted. All human people were alien to this Earth-planet when they were conceived and born into it. They cannot return to that alien infancy just as they (likely) cannot rightly claim to be made up of matter that is not part of this globe. Cultural ideas of a
post-lapsarian (after-the-fall) world are tied to this loss of innocence; or rather, growth from perfect potential to something definite and fixed. Fighting the "sinfulness" of growing-up, people have created systems of belief that further entrench notions of sameness and shared, common thought. When their child is born, a parent has the wonder-filled chance of re-living the alien state through its eyes. Everything is strange and new again. This is marvellous and also very frightening. How can this little creature survive in this harsh reality? The best chance of survival is acceptance into the congregation, uniformity, an inalienable birth-rite. The alien is not for this world.
The infant-alien is full of possibility, but perfectly ignorant. It is a stranger, but this is primarily due to the fact that everything is strange to it. It is not alien to its parents, at least, not on a basic level. The alien-ness is mainly metaphorical. Another type of alien to consider is the "outsider". This solipsist strives to remain other and alien in the face of insurmountable odds. The state to which this creature must return to refuel his flying saucer is equally hard to reach as
in utero. An egoist in a vacuum.
The Native American vision quest might be a used as an example of a cultural system grown up around the outsider. The quest itself alienates a member of the tribal group and sends them off, alone, to seek for answers of the spirits. Better examples are probably the criminal, the outcast, and the leper. Perhaps the best-known alien creature known to
homosapiens of the Earth spent most of its life among such as these. He taught them how to refuel, and how to get back home.