Plato was a philosopher in Classical Greece and the founder of the Academy in Athens, the first institution of higher learning in the Western world. He is widely considered the most pivotal figure in the development of philosophy, especially the Western tradition. Unlike nearly all of his philosophical contemporaries, Plato's entire work is believed to have survived intact for over 2,400 years. Others believe that the oldest extant manuscript dates to around AD 895, 1100 years after Plato's death. This makes it difficult to know exactly what Plato wrote.