I was thinking about the unspecified things around a sentence -- in Japanese you can just say "samui" (cold) and it's a perfectly good little sentence by itself. It means something's cold. You, me, some other guy, the outside world, take your pick. If the antecedent isn't clear from context then, well, you could ask.
You can do the same thing in English, naturally. "Cold!" you could say, which could also mean "I'm cold" or "you're cold" or "it's cold" or whatever. We tend not to think about it that way because it's grammatically incorrect. But, again, whatever.
And then I realized that *every* sentence is like that. There are always unspecified parts, as reading too much Noam Chomsky will tell you in detail. "He's standing on a table" leaves a *lot* out. It has to, because reality is complicated and doesn't actually divide up nicely into parts. You just naturally filter down from the unlimited number of possible things that could match that sentence ("Matthias is standing on a blue table", "The Lord God is standing on a stone table in Israel", "Bob has decided not to get another card from the dealer at the table", etc.)
It's like a prism. The sentence adds some restrictions on meaning, and then the listener's perception of reality filters in one side, and comes up with some other meaning on the other side.
As a speaker, you don't get to make a specific pattern of light. Not really. You can guess what the other person's light (reality) looks like, and set up a bunch of prisms hoping to make a picture on the other side... Good luck with that.