[wangchow]

Honestly, making things up is exactly how we prove if it works or not. For example:

Suppose I can talk into a tiny little device and someone can hear me from miles away.

That sounded like witchcraft at some point but it became a reality. Futuristic thinking needs to suppose lots of crazy-sounding things are possible.

[mikeash]

Compare with:

Suppose I can think into a tiny little device and someone can hear me from miles away.

That still sounds like witchcraft. Before one of them gets invented, or at least the basic underlying principles are discovered, how do you tell them apart?