This Buddhism is called 'Esoteric Buddhism', and it is differentiated from exoteric Buddhism because it places its viewpoint behind the part that appears on the surface of history (exoteric Buddhism).
それ以前の、歴史としておもてに表れた部分（顕教）の背後に視座を置くことからこの仏教を顕教から区別して「密教」という。