Touch based communication is a thing that exists. Some cultures count based on where they touch, for example, not by showing some number of fingers. The basics, however, involve consistency in the language taught. While there is no common, to my knowledge, touch based language it is possible for the basics of communication to be performed through touch alone and as long as the language was consistently used the individual would be able to learn it the same as sign language or spoken language. From that point it would be possible to bootstrap braille, and from there a more complex language model.