Obviously, assuming whatever means necessary to avoid mental defects and providing basic needs. Even language could be taught, perhaps through 'foraging robots' ;p
I disagree with the notion that humans cut off from civilization are immune to what we see as 'modern' behavior. All humanity came from the same source (regardless of evolution/creation) and all existing humans, most likely, have a least residual teachings, beliefs, traditions, whatever that modify behavior. The Amish are a very poor example, in the context we're talking about.
Edit: sure, it Wikipedia, but still:
Daniel Everett states that one of the strongest Pirahã values is no coercion; you simply don't tell other people what to do. There appears to be no social hierarchy; the Pirahã have no formal leaders. Their social system can thus be labeled as primitive communism, in common with many other hunter-gatherer bands in the world, although rare in the Amazon because of a history of agriculture before Western contact (see history of the Amazon).
Their culture is remarkably conservative. For example, they use canoes every day for fishing and for crossing the river that they live beside. However, when their canoes wear out, they simply use pieces of bark as temporary canoes. Everett brought in a master builder who taught and supervised the Pirahã in making a canoe, so that they could make their own. But when they needed another canoe, they said that "Pirahã do not make canoes" and told Everett that he should buy them a canoe.
Even these people have strong social order, which in and of itself is not altruistic, rather a simple means of 'you live your way so I can live mine' (i.e. selfish). Even the example given of the canoe "give us (me) something, even though I can do it myself".
I know I'm being overly simple, however I think the point is simple.
Smoke me a kipper, I'll be back for breakfast...