Chomsky writes, " one fundamental contribution of what we have been calling'Cartesian linguistics'is the observation that human language, in its normal use, is free from the control of independently identifiable external stimuli or internal states and is not restricted to any practical communicative function, in contrast, for example, to the pseudo language of animals " . " In short, animal'language'remains completely within the bounds of mechanical explanation as this was conceived by Descartes and Cordemoy " and the creative aspect of language is what separates humans and animals.