He erected rock pillars at Buddhist holy sites, but did not do so for the sites of other religions. He also used the word "dhamma" to refer to qualities of the heart that underlie moral action; this was an exclusively Buddhist use of the word. However, he used the word more in the spirit than as a strict code of conduct. Romila Thappar writes, "His dhamma did not derive from divine inspiration, even if its observance promised heaven. It was more in keeping with the ethic conditioned by the logic of given situations. His logic of Dhamma was intended to influence the conduct of categories of people, in relation to each other. Especially where they involved unequal relationships." Finally, he promotes ideals that correspond to the first three steps of the Buddha's graduated discourse. Much of the knowledge about Ashoka comes from the several inscriptions that he had carved on pillars and rocks throughout the empire. All his inscriptions present him as compassionate and loving. In the Kalinga rock edits, he addresses his people as his "children" and mentions that as a father he desires their good. Impact of pacifism After Ashoka's death, the Maurya dynasty declined rapidly. The various Puranas provide different details about Ashoka's successors, but all agree that they had relatively short reigns. The empire seems to have weakened, fragmented, and suffered an invasion from the Bactrian Greeks. Some historians, such as H. C. Raychaudhuri, have argued that Ashoka's pacifism undermined the "military backbone" of the Maurya empire. Others, such as Romila Thapar, have suggested that the extent and impact of his pacifism have been "grossly exaggerated". In art, film and literature Jaishankar Prasad composed Ashoka ki Chinta (Ashoka's Anxiety), a poem that portrays Ashoka's feelings during the war on Kalinga. Ashoka, a 1922 Indian silent historical film about the emperor produced by Madan Theatres. The Nine Unknown, a 1923 novel by Talbot Mundy about the "Nine Unknown Men", a fictional secret society founded by Ashoka. Samrat Ashok, a 1928 Indian silent film by Bhagwati Prasad Mishra. Ashok Kumar is a 1941 Indian Tamil-language film directed by Raja Chandrasekhar. The film stars V. Nagayya as Ashoka. Samrat Ashok is a 1947 Indian Hindi-language film by K.B. Lall. Uttar-Priyadarshi (The Final Beatitude), a verse-play written by poet Agyeya depicting his redemption, was adapted to stage in 1996 by theatre director, Ratan Thiyam and has since been performed in