David the Invincible (Classical Armenian: Դաւիթ Անյաղթ; reformed: Դավիթ Անհաղթ, Davit' Anhağt' ) was a 6th-century Armenian philosopher. He is best known as the author of several works including Definition of Philosophy and Exegesis of Aristotle. He was the member of Neoplatonic school and the founder of a non-religious branch of Medieval Armenian philosophy.