In 1948 Manos Hatzidakis shook the musical establishment by delivering his legendary lecture on rebetiko, until then with heavy underworld and cannabis use connections and consequently looked down upon. Hatzidakis focused on the economy of expression, the deep traditional roots and the genuineness of emotion displayed in rembetika, and exalted the likes of composers like Markos Vamvakaris and Vassilis Tsitsanis. Putting theory into practice, he adapted classic rembetika in his 1951 piano work, "Six Folk Paintings" ("Έξι Λαϊκές Ζωγραφιές"), which was later also presented as a folk ballet.