You might be interested in reading about the knowledge argument aka Mary's Room, a thought experiment about knowledge. See also: qualia

Basically this: Mary is a brilliant scientist who spends all day every day in her room. She has no color of any kind in her room. But, being a brilliant scientist, she has learned everything there is to know about color. She knows about frequencies and wavelengths, she knows all about the eye and the brain and how they interpret light to form the sensation of color. She has studied art from all of human history and knows how artists use color and understand all of their cultural associations.

But she has never seen red herself. So in all of her learning, does she really understand what red is? She's missing the qualia, the subjective experience of a thing. No amount of language and communication can bridge that gap.