I’m guessing the people who open this thread know what To Serve Man is all about. If not, here’s a brief summary.
Suppose the Kanamits had demonstrated their advanced technology for a few months, ending food shortages, solving the energy crisis, ending war, etc. and then come to the U.N. and said, “We have demonstrated our power to benefit your world and our willingness to share it. Now, in return, all we ask is that you supply us with a few hundred humans at a time so we can take them back to our planet and eat them. You are free to choose any humans you want, as long as they can survive the journey back to our planet. If you do not agree, we will take our technology back, and you will face the same problems with the same tools as before we arrived.”
If you think about it for a minute, it sounds like a pretty good deal. After all, 170,000 humans die every day anyway. There are probably enough people around who are suicidal, serving life sentences in prison, think it would be really cool to visit another planet, or believe it would give their death some meaning to actually volunteer to be treated to an all-expense paid vacation and then eaten.
Interestingly enough, I offered a very similar, but possibly more insidious variant (and a better deal for the aliens too) of the same question to my wife and friends last weekend over our weekly online gaming session.
The way I described it was that the Kanamits did much as you suggested, showed up, showed what they could do, and (modernizing the story a bit) could also offer biotech that promised to extend our useful effective age to 100 (fundamentally you age to full adulthood, and remain at that state until 100, without growing old, gotta keep that meat fresh you know!) and at that point, EVERYONE of that age was shipped off to Tasty Ghoul’s Fresh Meat Emporiums on the homeworld.
Just about all of us said yes, although a couple of the ladies did opine that they were not sure that under that regime they’d ever want to have kids, but they also said (and have proven IRL) they weren’t comfortable brining up kids in THIS world either.
“I just translated a Kanamit mathematics text; in their language, ‘hu’ is a prefix for ‘million’!”
Rod Serling: “Let this be a warning for those who sign contracts without clearly understanding the terms and conditions. In the jurisprudence of interstellar commerce, a single misinterpreted word is the difference between minor sacrifice and extinction. A cautious viewer should always retain not only expert legal counsel but expert translation before signing an agreement…in the Twilight Zone.”
A sort-of similar proposal was made by hostile aliens in the third series of Torchwood, called Children of Earth, though in this case the offer was for humans to hand over ten percent of the children or the aliens would destroy all humans.
Besides being morally abhorrent, there are so many other ways this could go severely sideways. For example; knowing humans, those in power would pick dissidents and other people they consider enemies. It could easily become a tool of terror.
“When you dine with the devil, you’d better bring a long spoon.”
My favorite variation on the OP’s whole concept is the Larry Niven short story “They’re Assimilating our Culture, That’s What They’re Doing!”, in which the human-eating alien creatures don’t take entire human bodies back to their homeworld – that’s too big a price to pay for transporting food when you have all the raw materials already at home. They get copies of our DNA and arrange to grow the parts they want to eat – arms, legs, hams, entire torsos for roasting, and the like. They get to eat human bodies but no human minds are ever traumatized. In return they offer us their technology, and all we have to do is sign on the dotted line. And, since they already have our DNA from surreptitiously obtained skin samples and the like, we may as well sign, because otherwise they’ll simply create bootleg copies of our body parts. The Evil human-eating alien invaders turn out to be damned civilized, if unscrupulous dealers.
There was a story I read once, called “Half the Battle”, in which humanity is trying to recover from an apocalypse. They’re re-creating old technologies, and the idea is, “We know it was possible back then, so there must be a way to do it now!”
That’s what I’d say. “Thanks for the proofs of concept, we’ll take it from here!” No more arguing amongst ourselves about “if” we can stop climate change, feed everyone, slow aging, all that stuff. Now, we know it’s possible, we just need to do the work.