Program music 1970s in particular experimented with program music, among which was Rush's "Jacob's Ladder" (1980), which shows clear influences of Smetana's "Má vlast" ("My Homeland") (1874-1879). In addition, Rush's songs "Xanadu", "Red Barchetta", and "YYZ" also show their experimentalism with program music, as do parts of "2112", particularly the discovery scene. Composers and some theorists argue that there is indeed no such thing as true "absolute ("ars gratia artis") music" and that music always at least conveys or evokes emotions. While non-professional listeners often claim that music has meaning (to them), "new" musicologists, such as Susan McClary (1999), argue that so-called
Ars Magna (Gerolamo Cardano) is square roots of negative numbers appear naturally in this context. However, "q"/4 + "p"/27 never happens to be negative in the specific cases in which Cardano applies the formula. Ars Magna (Gerolamo Cardano) The Ars Magna ("The Great Art") is an important Latin-language book on algebra written by Gerolamo Cardano. It was first published in 1545 under the title "Artis Magnæ, Sive de Regulis Algebraicis Liber Unus" ("Book number one about The Great Art, or The Rules of Algebra"). There was a second edition in Cardano's lifetime, published in 1570. It is considered one of the three greatest scientific