How we cite our quotes: (Chapter.Section.Paragraph) or (Chapter.Paragraph)
Quote #1
My view is that each particular mode of production, and the relations of production corresponding to it at each given moment, in short 'the economic structure of society', is 'the real foundation, on which arises a legal and political superstructure and to which correspond definite forms of social consciousness', and that 'the mode of production of material life conditions the general process of social, political and intellectual life'. (1.4.17)
Marx's view that economic life dictates (or mostly dictates) social, political, and intellectual life—the laws, people's ideas, religions, everything—is sometimes called historical materialism and sometimes called dialectical materialism. And sometimes it's called both.
Quote #2
The simple circulation of commodities—selling in order to buy—is a means to a final goal which lies outside circulation, namely the appropriation of use-values, the satisfaction of needs. As against this, the circulation of money as capital is an end in itself, for the valorization of value takes place only within this constantly renewed movement. The movement of capital is therefore limitless. (4.17)
When you as a non-capitalist buy a commodity and consume it, the product falls out of the sphere of circulation (the market) and is done with. But if you're a capitalist selling commodities in order to make more money, nothing intrinsic to that specific circulation act is going to bring you to a halt. Of course, other things might bring capitalism to a halt, such as climate change or running out of raw material.
Quote #3
For the transformation of money into capital, therefore, the owner of money must find the free worker available on the commodity-market; and this worker must be free in the double sense that as a free individual he can dispose of his labour-power as his own commodity, and that, on the other hand, he has no other commodity for sale, i.e. he is rid of them, he is free of all the objects needed for the realization of his labour-power. (6.6)
Ol' Karl is being a little ironic here. For capitalism to function, the worker must be free to sell his labor-power, which people are under capitalism, but weren't in other modes of production, such as feudalism. The worker must also be free of—that is, must not have—any stuff he or she would want to sell instead. Of course, if Karl had his way, workers would share the means of production in common, and the economic situation wouldn't require them to get exploited by selling labor-power. He's being sarcastic about the word free. Oh, Karl.