>Tell someone in the 1600s about the concept of cellphones and they would say it’s impossible to ever instantaneously communicate with someone around the world.
Plenty of empires (e.g. the Byzantines) had chains of fire signal towers (IIRC some had mirror signal towers). That's not instant, but it shrinks weeks of delay down to an hour, albeit with just half a bit of information. And the concept of going up a sufficiently tall mountain and being able to see a signal on the other side of the world is comprehensible to basically anyone (it's not physically possible, but they didn't necessarily know that).
Plenty of empires (e.g. the Byzantines) had chains of fire signal towers (IIRC some had mirror signal towers). That's not instant, but it shrinks weeks of delay down to an hour, albeit with just half a bit of information. And the concept of going up a sufficiently tall mountain and being able to see a signal on the other side of the world is comprehensible to basically anyone (it's not physically possible, but they didn't necessarily know that).