Or not. What I'd like to know is how deaf, from birth, people think. Concious thinking is having an internal dialogue with yourself. People who are mutilingual will tell you they think in their native tongue most of the time. Without speech how do the deaf communicate with themselves?
I don't think you're thinking the problem through or are you saying their internal dialogue consists of signing to themselves? When you think are you having a dialogue with yourself?
You seem to subscribe to the Sapir-Whorf hypothesis that thought cannot exist without language. Think about that for a moment. If thought requires language then how does a baby learn to speak, since learning a language clearly requires thought?
Sounds that represent things that are observed, are committed to memory. That is how language is learned. Thinking can be done in images, but words and other symbols makes it more efficient, and easier to communicate. Read the Helen keller story. Born blind, and deaf, her only sense of the world was her touch, her smell and her taste. But even with that limitation she experienced a break through when she make the connection between the woman teaching her, signing in her hand. This breakthrough was a catalyst that eventually led to her being schooled and even a writer. Once symbols that represented words, that represented things in reality, her brain was able to think using these tools. So one can think in images, but words allow much more complicated thought processes. One can think without words, language, just by memory showing you an action that you have done before and recorded it in memory. So that image of you doing that comes forth, and that is thinking. Thinking is basically the response of memory. Without a memory, one could not think.
