In Carl Sagan's Contact (the book, not the very good movie), Ellie is on the life-extension station with SR Hadden and about to land back on earth after the accident. I can't find the exact quoted exchange but it goes something like:

Hadden: Ellie, when you find them and talk to them, be VERY careful. These folks are old and their tolerances for risk may be alien to us.

Ellie: Well they sent us the Message, they obviously want to chat

Hadden: With beings that may be immortal or close to it, what we may consider a sure-fire bet may seem like an impossible risk to them. When they offer you something, you take it, you hear?

If someone can find the actual quote, thank you!

The closest approximation I can find is pp. 292--293. (I don't have a copy and haven't read it in about twenty years, so there may be a better approximation available.)

Hadden and Ellie have a brief discussion about the potential to market dying in space as a "really nifty last indulgence", whereupon Hadden segues to the topic of immortality and says the following:

"Now, I'm not bringing this up so I can boast. I'm bringing it up for a practical reason. If we're figuring out ways to extend our lifespans, think of what those creatures on Vega must have done. They probably are immortal, or close enough. I'm a practical person, and I've thought a lot now about immortality. I've probably thought longer and more seriously about it than anyone else. And I can tell you one thing for sure about immortals: They're very careful. They don't leave things up to chance. They've invested too much effort in becoming immortal. I don't know what they look like, I don't know what they want from you, but if you ever get to see them, this is the only piece of practical advice I have for you: Something you think is dead cinch safe, they'll consider an unacceptable risk. If there's any negotiating you get to do up there, don't forget what I'm telling you."

(Please forgive transcription errors.)

https://books.google.com/books?id=Q6o51-W_z8MC&lpg=PP1&dq=sa...

Perfect! Yes, this is the passage I was thinking of. Thank you!!!

The only civilizations we have known definitely show that contact involving a great technological difference is usually a disaster for the less advanced people. https://en.wikipedia.org/wiki/Fermi_paradox#It_is_dangerous_...

Scarcity is an important factor. Today, primitive societies (mostly) safe from Western conquest because they simply don't have anything we want.

That's more about selection bias than about anything that's inherently different about advanced societies today. There were primitive societies that did have valuable things [1], and they were all destroyed or conquered very soon after contact with more powerful societies, and they remain vulnerable to outsiders as soon as they come into possession of something of value. When gold was discovered on the land of uncontacted Amazonian tribes, for example, this happened: https://www.theguardian.com/global-development/2018/aug/22/a...

This is a pretty essential point that I think changes the calculus of contact quite a bit. A civilisation capable of visiting us at a reasonable expense to themselves would presumably have much easier access to near unlimited astroids/moons for automated mining.

So unless they really prize rare meat or have other illogical goals you wouldn't expect any aliens to visit us until its as easy for them as it is for us to take a transatlantic flight... I wonder if they're also arguing that they should stay silent to preserve our culture instead of curing our diseases etc.

The Dark Forest (Three Body Problem) explores this

Via video game, no less. Well, simulation-y video game. Sort of.