> the capacity to combine concepts in an infinitely recursive manner to represent an infinity of concepts and ideas. On top of that, we also posses the ability

> the capacity to combine concepts in an infinitely recursive manner to represent an infinity of concepts and ideas. On top of that, we also posses the ability to communicate (verbally, through sign, or more recently through writing) those combined concepts in such a way that other humans can then recreate that concept in their own mind. We don't know that animals can't. We know that some animals can convey detailed information very extensively, but we don't know the structure of the communication well enough as to claim that it isn't via something equivalent to human language. Crows, for instance, can inform other crows about specific people, or characteristics of people, without those things being present. That would generally require descriptive communication to do, which inherently implies an abstraction. Where's the line between that and human language?