[kabdib]

Like: "I know we could teleport. No, I didn't see any massive power supplies, it was just a box about the size of your 'car' and it cost as much as a loaf of bread to use it." or "I called my sister on Alpha Centauri every Sunday, and we'd chat about the weather."

Just knowing it's possible, with gross engineering parameters, can be half the battle.

[rmc]

Even knowing some of the specifics would be helpful. Imagine a non-engineer from now going back to 1500s and talk about flying.

They can say that you need 2 wings on the side, and you need to go really fast in a straight line before you can take off. Sometimes you can see the little flaps on the edge of the wing move up and down. Though you can also do it with little planes. And if you want rotating blades then it has to be smaller than planes (helicopters).

This should help a clever person (e.g. Leonardo da Vinci) figure out how to fly.