The Czechs are described as a very cultural nation which has contributed to the world a large number of prominent figures. The most significant rulers and heads of state include emperor Charles IV and presidents T. G. Masaryk, Edvard Beneš, and Václav Havel. Names of world renown include Jan Amos Komenský (Comenius) “the Teacher of Nations“, scientists Jaroslav Heyrovský (Nobel Prize laureate for chemistry), Otto Wichterle, a Czech chemist who invented contact lenses, and Antonín Holý (professor of honour in medicinal chemistry), who discovered drugs against AIDS. Famous people of culture include composers Bedřich Smetana, Leoš Janáček, Antonín Dvořák and Bohuslav Martinů, writers Franz Kafka, Karel Čapek, Jaroslav Seifert (Nobel Prize laureate), Jaroslav Hašek, Bohumil Hrabal, and Milan Kundera. Winners of the American Academy Award are film directors Miloš Forman (born in former Czechoslovakia), Jiří Menzel, Jan Svěrák, and the singer Markéta Irglová. Painters to be named are František Kupka and Alfons Mucha. Athletes of world renown include Emil Zátopek, Petr Čech, Jaromír Jágr, Dominik Hašek, Pavel Nedvěd, Jan Železný, Kateřina Neumannová, Martina Sáblíková and many others. Petra Kvitová, Martina Navrátilová and Ivan Lendl are also of Czech origin.