In a nutshell, what is OWL Horst reasoning compared to other types of reasoning? Where does it fit on the expressivity vs performance scale? How does it compare to, say, the reasoner choices in Jena? How popular is it? How necessary is it if you have one or more other types of reasoning available to you in a reasoner? In formal circles, OWL Horst is called pD*. You'll see it called the former by i