Two general kinds of motivations are in play in these diverse forms of struggle within and over capitalism: class interests and moral values. You can oppose capitalism because it harms your own material interests, but also because it offends certain moral values that are important to you.

There is a poster from the late 1970s that shows a working-class woman leaning on a fence. The caption reads: “class consciousness is knowing what side of the fence you’re on; class analysis is figuring out who is there with you.” The metaphor of the fence sees conflict over capitalism as anchored in conflicts of class interests. Being on opposite sides of the fence defines friends and enemies in terms of opposing interests. Some people may be sitting on the fence, but ultimately they may have to make a choice: “you’re either with us or against us.” In some historical situations, the interests that define the fence are pretty easy to figure out. It is obvious to nearly everyone that in the United States before the Civil War, slaves were harmed by slavery and they therefore had a class interest in its abolition, while slave owners had an interest in its perpetuation. There may have been slave owners who felt some ambivalence about owning slaves—this is certainly the case for Thomas Jefferson, for example—but this ambivalence was not because of their class interests; it was because of a tension between those interests and certain moral values they held.