PIE is the language that the word Kjrsos comes from.  An ancient language that there is no record of. A language reconstructed by linguists from around the world.  A language that was in existence when we first bonded to horses and began to ride.   It is in understanding our common past, the immense history, a civilization built upon the horse, the centuries of a relationship that still defines us today, that we can begin to appreciate how astounding how all of those connections through all the generations and changes through human history is a part of us.