A nation that enslaves another forges its own chains.

The redeeming feature of war is that it puts a nation to the test. As exposure to the atmosphere reduces all mummies to instant dissolution, so war passes supreme judgment upon social systems that have outlived their vitality.

There is no greater stupidity than for people...to marry and so surrender themselves to the small miseries of domestic and private life.

Once the inner connection is grasped, all theoretical belief in the permanent necessity of existing conditions collapses before their collapse in practice -- Letter to Ludwig Kugelmann (July 11, 1868)

Music is the mirror of reality.

A man cannot become a child again, or he becomes childish.

Free education for all children in public schools... Combination of education with industrial production