This used to be here some years ago, some further explanation on an early 2010 post Marc made me expand. It seems to be still valid, so I'm re-posting it.Some background: Text linguistics defines a couple of concepts: thema and rhema. Broadly, the first is the subject we're talking about, with all the information we already know, while the second is what information the text adds to our knowledge. So, if I say "Ted's cat is sick", the sentence is build so that you already know Ted and his cat. You didn't, however, know it was sick until I told you. However, you might not know Ted had any kind of pet, in which case "Ted has a cat" would be part of the thema for me but part of the rhema for you. If I later say "Ted's asked me to get his cat from the vet because he's busy" you already know that I'm not getting the cat back from a standard health check. "The cat is sick" has gone from rhema to thema. If we are to communicate, my thema and yours have to be at a similar level (you can bridge the gap "Ted has a cat", as long as you know Ted and you know what cats are). OK, let's assume Albert, Bob and Clara. Albert is a nice guy that has discovered how to let things be the hard way. He's been beaten, he has beaten others, and had some harsh talks, back in the day, with cops that knew he was up to no good. He's since reformed and leads a picket fence life at some unassuming neighborhood far from his old place. Albert is a sage, without much skill at talking but a lot of experience. Bob is a former jock with a stint in the army, who never saw physical exercise beyond boot camp but has convinced others that his bar fights are the real thing; he's even done some competition in some contact sport or other. He's been doing it for so long that he believes it himself, mostly, and it pays well. Much better than flipping hamburgers, at least. He's a seller. Clara had a scare many years ago that shook her world. She has no big stars to her violence curriculum, but she's spend every day since thinking about violence, how it happens and when it happens. She enrolled as a reporter for some local newspaper in the state capital and interviewed lots of victims, criminals and cops. She has written a book, "Stay safe", that has quietly become a must read in certain circles. She's also a sage of a sorts, even if most of her experience is second hand, who knows she still lacks a lot of violence experience but has a tremendous skill showing others part of what's out there. That's a bard. Now, you come in. For whatever reason, pick one, you have chosen to learn self defense. Albert lives nearby, and you kinda sorta guess "he's had a life" --suspected it since the day he stopped a gang of punks who were harassing old Miss Dandelion with his mere presence, but you couldn't quite set that thought--. You haven't talked much, though, and you hesitate to ask. You visit the local franchise of the ATA and they have an add: Bob is teaching a seminar in a couple of weeks. 4 hours saturday evening for 200 $. You go back home, browse the net, and find his name is well-regarded. He's even got a website. On it, you find a short article that quotes a book. You don't have that book, but the quotes seem to ring a bell, and they sound legit. It is then that you remember those same sentences, here and there, in some conversations with Albert. You take a dive and ask him about it next time you find him mowing the lawn. He doesn't say a thing, but he leaves the mower and goes into his house, coming back with a thin, earmarked book, tattered from use. Clara's. Now, realize that the underlying information is the same in all cases. Albert, Bob and Clara are talking about the same, they're even using the same sentences. However, the information you get is not the same. Albert knows Clara's right, but he can't transmit it properly. Bob doesn't have a clue, but he's found some sentences in that book that, as he reads it, reinforce his beliefs and provide him easy answers, out of context, to people's fears. He knows people are not going to read the book... at least not until they've paid those 200 bucks. Clara doesn't know much. She's been in less violence than Bob, even, but she's got a good point of view, she's made a real effort to understand it and she's a superb writer. Albert, Bob and yourself need Clara, but for completely different reasons: Albert needs someone to teach you the right background. What's completely alien for you is something he grew up with, so much part of his life that he cannot separate it enough for an explanation. Without some common background, communication is impossible. Bob needs Clara, too, to justify his approach and his prices. But he's going to twist it as much as he needs. You need Clara to see what's out there. Realize, also, that it's easier to go with Bob: he's already digested the book for you. 200 bucks and an afternoon of your time, and that's all. Albert will not ask you a single dollar, but he'll talk about things that the book only glimpses at, good as it is, and will stretch you brain until it hurts. Most people don't know an Albert. That's why Clara has to be real careful about how she writes. Most people who read her book will either have no idea or will come from Bob's mindset. Bob has already managed to pervert her words, but she wrote that to help other people, so she must work, hard, to clear any misunderstandings to the people who reach her work having read only selected, out of context, modified soundbites. Take care.