A Greek archaeologist believes he has discovered the tomb of Aristotle. Konstantinos Sismanidis, who has been painstakingly excavating the ruins of Stagira since 1990, told CNN his team has very strong evidence the 2,400-year-old tomb belongs to the great philosopher. Sismanidis said the structure, about 40 miles east of Thessaloniki, was built to honor Aristotle's death in 322 B.C.