The contrast with animal communication systems, for example, is notable.
Briefly, animal communication system seem to be of two sorts. First, birds (and apparently nonhuman primates) have a fixed and fairly small repertoire of distinct signals, each of which has a set function: flight call, alarm call and the like.
A particular environment elicits the appropriate response. Human language does not consist in such a small fixed repertoire of predictable responses.
Second consider bees. A bee returning from a distant food source dances a message. The positioning of the dance and its pattern indicate the direction and distance of the food source.
This remarkably efficient system of communication differs from those of birds in having an limited number of signals: the length and the pattern are capable of indefinitely many variations.
Nevertheless, the bee’s system is not flexible in the way human language is. Each response is environmentally fixed: if you know where the bee has been and if you know the coding system, you can predict the pattern of the dance.
In contrast, of a person comes from a food source – a good restaurant for example – you cannot predict her words.
Her food description indeed, whether she talks about food at all – is stimulus independent.
Stimulus Independent of Language
