Symphony, K. 75 (Mozart) works from this time period, such as the K. 97 symphony, the autograph, which was in the possession of Breitkopf & Härtel, was destroyed during World War II. Mozart's authorship therefore remains uncertain. Most professionals consider the work authentic. The Alte Mozart-Ausgabe (published 1879–82) gives the numbering sequence 1–41 for the 41 numbered symphonies. The unnumbered symphonies (some, including K. 75, published in supplements to the Alte-Mozart Ausgabe until 1910) are sometimes given numbers in the range 42 to 56, even though they were written earlier than Mozart's Symphony No. 41 (written in 1788). The symphony K. 75 is given
19th-century philosophy Stuart Mill promoted the idea that actions are right as they maximize happiness, and happiness alone. Developed by Karl Marx and Friedrich Engels in the mid-to-late-19th Century, Marxism is a sociopolitical and economic view based on the philosophy of dialectical materialism, which opposes idealism in favour of the materialist viewpoint. Marx analysed history itself as the progression of dialectics in the form of class struggle. From this it is argued that "the history of all hitherto existing society is the history of class struggles." According to Marx, this began with the phase of primitive communism (hunter-gatherer society), after which the