Language exists as a tool to facilitate empathy

Language evolved as a tool to facilitate empathy.

Language is a means of communication. 

Of course, just because you can empathize with a person doesn't mean that you agree with them.  Far from it.  And here language can be useful, too - to establish clearly how two people disagree, to clarify the differences between their points of view.  This, too, is a form of empathy, and an important one.  If you assume that everyone else's perspective is exactly the same as yours, you aren't really empathizing with them.  The difficulty - and the importance - of empathy lies precisely in the ability to empathize with people who are different from you.

I am tempted to play something like a Wittgenstinian game here, that is, to derive from this empirical claim a normative injunction: that any attempt to use language for any purpose other than the facilitation of empathy constitutes a misuse of language (in something like the way that Wittgenstein's epigones like to claim that certain traditional philosophical questions are meaningless and that to ask them constitutes a misuse of language).  That is, any lack of clarity in communication constitutes a misuse of language.  I think there are some analytic philosophers who might say something like that.

But no - I will not make that normative claim.  Evolution by natural selection is not teleological.  I would not claim, or even imply, that the "purpose" of language is to facilitate empathy, and that to deviate from this purpose is somehow wrong.  There are many instances in evolution where a trait that was selected for its adaptedness in one capacity is repurposed for something quite different.  For instance, the ancestors of bats likely used the patagia - the webbed skin between their fingerlike digits - to hunt insects, almost like a fly swatter.  They may have been used, also, in signalling, perhaps in mating rituals.  Later, these tree-climbers may have accidentally discovered that spreading out their patagia could slow a fall, almost like a parachute.  From here, the patagia evolved into machines for gliding, and ultimately flying.  Similarly, the air sacs that certain early aquatic vertebrates used for buoyancy in water may later have been repurposed for breathing on land - that is, they evolved into lungs.  The aquatic ancestors, of course, did not need lungs, because they breathed water, not air, through their gills.  Maybe something similar is happening with language: it evolved as a tool for facilitating empathy, but as it turned out, it can be put to other uses as well.  As a case in point, my favorite novelist, William S. Burroughs, seems to have been an extraordinarily empathetic person, who used language not to increase his empathy - his prose style cannot be considered particularly clear communication - but rather to establish his independence.  As such, his tropes often serve to subvert communication - and the communities that are established through communication.  So be it.