Private property

Under private property ... Each tries to establish over the other an alien power, so as thereby to find satisfa­ction of his own selfish need. The increase in the quantity of objects is therefore accompa­nied by an extension of the realm of the alien powers to which man is subjected, and every new product represents a new potenti­ality of mutual swindling and mutual plunder­ing.

Marx, Human Require­ments and Division of Labour (1844)