Whereas Piaget gave very little importance to language, in the development of thought. Vygotsky and Piaget had a fundamental disagreement about the relationship between language and thought. Piaget (1923) argued that early language is egocentric and only becomes socialised with cognitive development. He suggested that the pre-operational child fails to take into account the other person's view and as a result, the early conversations of children have more of the quality of monologues than of dialogues. Onlywith cognitive development does speech take on a genuinely communicative function. According to Piaget's theory, language and communication depend on the development of thinking. Vygotsky argued, on the contrary, that language is communicative from thebeginning. He carried out an ingenious test of his theory. He compared the amount of `egocentric` speech when hearing pre-school children together, with the amount of speech produced when the hearing child is placed in a room with a group of deaf-mute children.