I don't think communication exists
Bollocks. You're communicating right now.
Since you're a fan of formal definitions, you can find some here:
http://en.wikipedia....i/Communication and
http://www.merriam-w...y/communicationThose even use only words, so I am comfortable in trusting that you should have a reasonably high degree of confidence that they are less ambiguous and an accurate definition of the word, communication.
What you've done is created a model of what you think communication is. What I think I see, however, is a belief that your model is accurate because it's what you created, and you demonstrate the typical human quality of assuming that because you logically deduced it, it must be true (since otherwise there's cognitive dissonance, something the brain isn't too fond of and tries to reconcile by either excluding perspectives that do not align as being somehow incorrect or not applicable, or shifting one's own perspectives to be in alignment with the new set of information).
Communication, which as defined is an expression of information, messages, or thoughts by means of speech, visuals, writing, signals, or behaviour, is a function of each of those elements. One could even argue that it is gestalt; it's greater than the sum of its parts.
When communicating, it's the sum of all the speech, visuals, writing, signals, and behaviour that are present. Using only words means that the other aspects of communication have been omitted, but not that they are irrelevant. They provide additional information and context which may be essential to understanding the message being expressed. Depending on the message being expressed, they may not.
Using only words does not remove ambiguity. As with all communication, ambiguity only exists since the speaker and the listener are two different people. With full understanding of myself, I never find the things that I
write ambiguous. Especially not as I write them. That doesn't mean that
everyone else will understand the message I am expressing.
There's the obvious barriers: language. If I don't understand the language, the words expressed to me are meaningless. However, based just on experience, I have successfully communicated to people despite not understanding the language (I have a funny story about being in a hospital in Punta Cana). Clearly communication doesn't require words. Therefore, it must be possible to communicate without words.
There's also cultural nomenclatures. Colloquialisms that exist in one part of the world, but not the other, despite the same use of the language. These may even evolve within the same culture. Say "humbug" now in the UK, and you get a different reaction than you did a couple centuries ago. Sometimes the same word can mean different things depending on time and location. There's one famous curse word that has a plethora of applications.
When people try to be as unambiguous as possible with their words, it rarely comes across as natural. You'll tend to see this sort of stuff in legalese in binding contracts and so forth. The attempt to remove ambiguity is essential to making sure the terms of the contract are clear for all parties, and perhaps more importantly, in the court of law. This ambiguity is not guaranteed, however, and often requires more than a single person to contribute to it in order for it to be done so.
Even if one has an infallible trust in the ability for men to communicate in unambiguous ways using only words, reality doesn't reflect that. In this point, it simply becomes a logic experiment that contemplates a model that is not an accurate representation of reality. This can be useful sometimes (physical sciences always create models to help simplify situations for ease of understanding - friction was rarely something considered in my Physics classes, but it always exists in reality).
Words in communication have always been imprecise. For example: "I think the movie Pearl Harbour was fantastic" If I give you only one chance to describe what I am trying to express with that sentence, can you be
absolutely certain that you'll be correct and that there isn't some other message I am trying to express?