"The philosophers have only interpreted the world, in various
    ways; the point, however, is to change it."

    - Karl Marx (1818-1883), "Theses on Feuerbach" (1845).

   "Men can be distinguished from animals by consciousness, by
    religion or anything else you like. They themselves begin to
    distinguish themselves from animals as soon as they begin to
    _produce_ their means of subsistence, a step which is
    conditioned by their physical organisation. By producing 
    their means of subsistence men are indirectly producing 
    their actual material life."

   "What they are, therefore, coincides with their production,
    both with _what_ they produce and with _how_ they produce.
    The nature of individuals thus depends on the material
    conditions determining their production."

   "[M]en, developing their material production and their 
    material intercourse, alter, along with this their real
    existence, their thinking and the products of their 
    thinking. Life is not determined by consciousness, but
    consciousness by life."

    - Karl Marx (1818-1883), The German Idealogy (1845-46)

   "Modern industry has converted the little workshop of the 
    patriarchal master into the great factory of the industrial 
    capitalist. Masses of labourers, crowded into the factory, are 
    organized like soldiers. As privates of the industrial army 
    they are placed under the command of a perfect hierarchy of 
    officers and sergeants."

   "No sooner has the labourer received his wages in cash, for the 
    moment escaping exploitation by the manufacturer, than he is 
    set upon by the other portions of the bourgeoisie- the landlord, 
    the shopkeeper, the pawnbroker, etc."

   "The development of modern industry...cuts from under its feet 
    the very foundation on which the bourgeoisie produces and 
    appropriates products. What the bourgeoisie, therefore, 
    produces above all are its own grave-diggers. Its fall and 
    the victory of the proletariat are equally inevitable."

    - Karl Marx (1818-1883) and Fredrick Engels (1820-1895), 
      Communist Manifesto (1848)