Language is just specific expression. It evolves alongside the human brain as we become more and more socially complex, we needed to be able to express ourselves or information to each other which wasn’t easy with things like grunts and pointing. Things like facial expressions are some of the earliest examples of pre spoken language, with which one could express emotion, as it is not only the foundation of humanity’s perception, but also effective at giving others enough info to infer where to look for something. This could be why it is so innate a language within the human mind that even people across different cultures can comprehend. But even that isn’t enough to express everything and so eventually spoken then written language evolved, allowing us to be specific with each other and allowed us to evolve into societal beings rather than pack animals. Each type of language has its own quirks from its evolution, and will continue to evolve. Some languages allow specificity in ways incomprehensible to those who don’t understand the language itself, gendered languages being one such example. A gendered language allows one to apply societal constructs and in a way stereotypes to objects in a way that allows metaphor to imply information. Another more mundane example of this same type of implicit metaphor that may be better understood by one who doesn’t speak such a language is tone. This is implied just as facial expression implied what spoken language would one day become. It will be a wonder to see where language evolves in the future, especially as technology augments our ability to transfer and encode information, as all any of that really is is just information.
EDIT: Just fyi I did make all this up and have no qualifications to say any of this, but it seems right and accurate so please someone prove me wrong, otherwise I will assume my deductions are correct.
That’s just a normal shortcut for mental math. Break your problem into simpler problems then combine, in this case if one wants to know 7+6 this is being turned from 7+7=14, an easy problem to remember, into (7-1)+7=14-1=13.
That doesn’t feel exactly right as it’s not exactly the way you think about it, but words can’t describe such inferences of thought other than to call them what they are which is not exactly how one’s thoughts reflect them.