"I requested further that religion should be criticised in the framework of criticism of political conditions rather than that political conditions should be criticised in the framework of religion, since this is more in accord with the nature of a newspaper and the educational level of the reading public; for religion in itself is without content, it owes its being not to heaven but to the earth, and with the abolition of distorted reality, of which it is the theory, it will collapse of itself. Finally, I desired that, if there is to be talk about philosophy, there should be less trifling with the label “atheism” (which reminds one of children, assuring everyone who is ready to listen to them that they are not afraid of the bogy man), and that instead the content of philosophy should be brought to the people. Voilà tout."
http://www.marxistsfr.org/archive/marx/works/1842/letters/42_11_30.htm
"When the ancient world was in its last throes, the ancient religions were overcome by Christianity. When Christian ideas succumbed in the eighteenth century to rationalist ideas, feudal society fought its death battle with the then revolutionary bourgeoisie. The ideas of religious liberty and freedom of conscience merely gave expression to the sway of free competition within the domain of knowledge.
"Undoubtedly," it will be said, "religious, moral, philosophical, and juridicial ideas have been modified in the course of historical development. But religion, morality, philosophy, political science, and law, constantly survived this change."
"There are, besides, eternal truths, such as Freedom, Justice, etc., that are common to all states of society. But communism abolishes eternal truths, it abolishes all religion, and all morality, instead of constituting them on a new basis; it therefore acts in contradiction to all past historical experience."
http://www.anu.edu.au/polsci/marx/classics/manifesto.html
http://www.marxistsfr.org/archive/marx/works/1842/letters/42_11_30.htm
"When the ancient world was in its last throes, the ancient religions were overcome by Christianity. When Christian ideas succumbed in the eighteenth century to rationalist ideas, feudal society fought its death battle with the then revolutionary bourgeoisie. The ideas of religious liberty and freedom of conscience merely gave expression to the sway of free competition within the domain of knowledge.
"Undoubtedly," it will be said, "religious, moral, philosophical, and juridicial ideas have been modified in the course of historical development. But religion, morality, philosophy, political science, and law, constantly survived this change."
"There are, besides, eternal truths, such as Freedom, Justice, etc., that are common to all states of society. But communism abolishes eternal truths, it abolishes all religion, and all morality, instead of constituting them on a new basis; it therefore acts in contradiction to all past historical experience."
http://www.anu.edu.au/polsci/marx/classics/manifesto.html