If I learned one important thing in college (and I like to think I do because otherwise I wasted a lot of time there) that important thing is how to measure things.
You may think that you don't need to go to college to learn that, and you are right, but the interesting bit, if I may sound like a social studies major for a few seconds, is how arbitrary measurements are. They are the one bit where all that "reality is a social construct" insanity is kinda true.
Consider the distance between two places. ¿How far is my house from my mother's?
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Well, google says it's 447km away. But you already know that's not true! If I were to go by, say, helicopter, or unstoppable tank, I may be able to take a somewhat shorter path. Were I to use the Underminer's tunneling machine, I could take an even shorter path.
But all that is mostly changing paths, so you may still feel some confidence that you know how far my mom's house really is, except that we just may not be able to take a specific path, but the distance is a "real" thing.
But geographical, geometrical distance is only one way to measure. There are other metrics, and they may be more or less valid. For example, my mother's house is 6 hours away by bus.
It's also U$S 60 away by bus, U$S 30 by car. Unless I take my son with me, in which case it' U$S 120 by bus, but still U$S 30 by car.
And if I really really want to go there, it's an impulsive decision away, and i I don't really want to, there is a whole lot of convincing between here and there.
And if I were as poor as I once was, then maybe it's infinitely far away because there is no way to get there from here.
When someone says "the world is smaller now" that's not metaphor, that's maths.