A perfect match

I think it's great if you are able to share your office with a colleague. Not only do you have someone to cheer you up when you're sad or feel lonely, but this someone is also the quickest source of information. Every day something comes up which needs to be consulted; a student uses a seemingly weird collocation in her writing, and you don't want to dismiss it until you're perfectly sure it's incorrect. This discussion about correctness and incorrectness may lead to new bits of knowledge, on both parts. 

I remember this situation: my colleague was hunched over a student's essay describing the future world, wracking her brains with a sentence he had used. She understood what the student had meant to say but couldn't help feeling something was not right with the wording of the sentence. She wanted to help the student but couldn't find an appropriate way of paraphrasing his idea. As dictionaries or Google were useless in this case, she asked me. I remember the sentences I came up with was something along these lines: In the future, people will stop manipulating each other. This version was happily approved by my colleague, but she added kindly: "You mean: manipulate one another, but thanks, this is perfect". I replied with a question, a little bewildered: "Why not manipulate each other?". She answered, trying hard not to sound arrogant: "Well, you can't say each other, you know, because we use this when we're talking about two people". She went on to say: "I remember, as if it was yesterday, when I was in England 20 years ago, our teacher, a native speaker of English, put this particular rule on the board. I can still visualize it clearly, after all those years - the board was divided into two columns and ......"

I realized that I had come across this rule before, and I admitted that I'd probably forgotten about it. I felt a little ashamed that I might have used incorrect language multiple times in the classroom. However, I could swear that I'd heard people use each other when talking about many people - it just sounded so natural to me. So I went and looked it up on the internet, and this came up

To cut it short, my colleague finally acknowledged the fact that it was acceptable to use each other in the sense we'd talked about. But that's not the point I'm trying to make. What is really important is that we both learned something valuable from this short exchange of opinions. My colleague reminded me of a rule I was once familiar with (now I'll be able to explain to my students if they ask), and she realized that language evolves and rules come to existence to be ultimately violated by its users. 

A similar discussion we've had was about the possibility of using but at the beginning of a sentence. I remember my colleague was about to underline this as a mistake in a pre-intermediate student's essay because she was convinced that it was not correct to start a sentence with But. Before she did though, she stopped and checked with me first. I could swear that I'd seen it used this way a million times in written work of native and non-native users of English producing language high above the pre-intermediate level of proficiency. So I checked here:

Once again, I was truly amazed by my friend's long-term memory capacity. She mentioned the same language course she participated in when she was studying in England back in the 90s. However, I was glad that my intuition wasn't wrong either, and I realized that my colleague and I are a perfect match; she remembers the rules and I have the hunch .....