I know she knows words because she responds appropriately to what I say. She moves and acts in ways that are consistent with what I ask her to do. I'll say, "Go give that to mommy," and she will do just that. So I know she understands what I'm saying.
If she understands what I'm saying, and she understands what she is saying, then she doesn't seem aware that we don't understand what she is saying most of the time. I can hear her say parts of words, but not all of the word she is trying to say. She probably hears the words in her head and understands the meaning of what she wants to say, but she doesn't have full motor control of her mouth to form each sound yet. I wonder if she knows that this is happening. Probably not.
The following video shows my daughter having a conversation with me. Have a look.
As you can see from the video, she can wax eloquent while speaking what sounds like gibberish to us. She seems fully aware of what she wants to say in her own mind, but doesn't know that what is saying is unintelligible to me. Notice that she knows where Mommy is and where the snow is.
As she grows older, she will learn to form the words and all of us will marvel at the first time she can say something that all of us can understand. At that point, she will use words more and more to get her needs met rather than gestures and just sounds.
I offer this example not just to show Emily's development. I offer this also to make a point. Some people never grow out of this phase, but with a twist. Some people can say what they understand, but will be completely unaware that other people don't understand what they are saying. There is a break down in communication from within the brain where there is know acknowlegment.
To put it differently, what I am saying in a conversation requires context to be understood. No one can get inside my head to understand the context of what I'm saying, just like I can't know the context of what Emily is saying because her worldview is so completely different than mine.
This is a problem on many levels, from personal to geopolitical. I've seen this while observing the discord between the two dominant parties, the Democrats and Republicans. When Democrats try to talk to Republicans, the Republicans are listening to what is said in an entirely different context than what the Democrats are thinking. The reverse is true, also.
It is not easy to take communication in context. I have this problem and I'm a pretty active listener. Active listening is the mental task of asking questions without saying them, while listening to what is being said. As someone who is hard of hearing, I try to take in everything, body language, tone, pitch, rhythm - any clues I can find to understand what people are saying. I use that information to establish context.
When we're dealing with an adversary, we may be more concerned with getting what we want than actually listening. This can impair our ability to negotiate because we can't understand what others are saying in the context of what they want, what they see as right. We hope that a 3rd party can act as arbitrator so that we can be sure what we're saying is properly understood by the adversary in context.
I know this from my own experience. I've written letters and said things to other people, that later, when I asked them about it, they said they didn't understand what I was saying. Upon hearing that, I found myself bemused and a little bit confused. I thought they understood, and had that sense about me for weeks, even months only to find out that the other person had no clue what I was talking about.
This lack of understanding can be innocent or intentional. Sometimes, people can choose to say, "La la la, I can't hear you!" Other times, we think we understood what was said to us, when we didn't.
Person to person, nation to nation, we find that communication, in all of its forms, is the foundation for peace. We can't just say what we want to say, we need to get acknowledgement that what we said was understood. We might ask, "What was the middle part again?"