[quote]You begin with the assumption they would prefer to have our technology.[/quote] No, I do not. I only offer a scenario where this may be. And if we do not give them the opportunity to decide on this for themselves, we are engaging in an act of cruelty. [quote]All the cultural exchange you speak of happened because cultures branched out. Isolated peoples left obviously have little desire to do so, or they would have in the last 20,000 years or so.[/quote] Perhaps, and this may well be the case for some or even most. I'm not an expert on reasons for migration. Perhaps some cultures found regions that were adequate enough to support a small community, but not enough to sponsor overpopulation and a need to expand, migrate or make a desire to contact any outside culture. And yes, some cultures have rejected interaction, and this isn't too surprising as even more "modern" cultures in recent history have attempted isolationism. I'm not arguing whether or not cultures should be forced to deal with the fact they're not alone on the planet (that's a different point altogether, although you keep accusing me of making that point here). I'm arguing that uncontacted cultures should be given the chance to understand what advancements have been made for humanity as a whole, and that these advancements could not just be given to them, but taught to them, and most importantly, could be made/invented by them themselves. To restate, I make the distinction between contacted cultures and uncontacted cultures. [quote]and that we would be forcing them to deal with a culture destroying reality[/quote]When Europeans first made contact with Native Americans, they perceived us as riding islands to their land, our items as holy artifacts, and us insane for eating the blood of Man. These so-called culture destroying realities didn't destroy anything; our items, beliefs and culture were easily integrated, our guns were used for hunting by Native Americans centuries before the American Revolution, and when Columbus arrived they were already so familiar with these realities that they rowed to him before he even made it to shore in under to undergo trade. I think you and our society as a whole overestimate how culture-destroying new truths may be. [quote]but I cannot be certain they would choose to live longer in a modern world in which they have nothing, or go on within their own society they have created for themselves.[/quote] I didn't say they had to or should move in to "our world," either, though if they wanted to do that, that's their choice. It could be as extreme as that, offering them a home in our cities or in some government-funded reservation of sorts, or something simple as offering them additional resources, possibly through small trade; iron so they could build stronger tools, food in bad times, domesticated livestock, etc. Or anything and everything in-between.

We have plenty of technology to help us watch them without them knowing it. Don't think that would be a big problem. Collecting DNA without disturbing them probably wouldn't be too hard either. We leave it pretty much everywhere. Just follow a group of hunters and collect some hair/blood they leave behind after they are gone. I think it would be best to try to leave them intact just in case future researchers could use them to discover more than we can learn from them already.