Greek drama was originally entirely performed by choruses. According to tradition, the Greek dramatist Thespis, of the 6th century B.C., was the inventor of tragedy and the first to write roles for the individual actor as distinct from the chorus, and the actor's exchanges with the chorus were the first dramatic dialogue. Since Thespis himself performed the individual parts in his own plays, he was also the first true actor. Ever since choruses disappeared from drama, thespians have filled all the roles in plays. Thespian is also an adjective; thus, we can speak of "thespian ambitions" and "thespian traditions", for example.