Turning an enemies rhetoric against him. So my May Day sign is, "capitalists are the real moocher class." Which goes off the republicans calling black peo (ahem) welfare receivers moochers.
Second best
People who favor capitalism often attempt to justify it by saying 'that as long as it offers mobility, then its okay', which is like saying 'slavery is justified if slave masters have the chance to be slaves and slaves be slave masters'. This concept of 'mobility' has been invoked way too much in my advanced labor economics class, that is really getting a bit annoying. Although it is a ridiculously funny argument.
Adding; its largely because they miss the point that capitalism is an exploitative social relationship, and it doesn't really matter if the population consists of 99% proletariat and 1% bourgeoisie, or 80% proletariat and 20% bourgeoisie, and so on (with the latter numbers suggesting more upward mobility).
My favourite rhetorical device is axiomatic statements that take the form of "the X of Y/ the Y of X"
As in:
The Poverty of Philosophy
Decadence: Theory of Decline or the Decline of Theory?
Philosophy is simultaneously the thought of alienated power and the power of alienated thought.
etc.
~J.
Situationist double speak! I love it!
People who favor capitalism often attempt to justify it by saying 'that as long as it offers mobility, then its okay', which is like saying 'slavery is justified if slave masters have the chance to be slaves and slaves be slave masters'.
Some one basically said that slavery is justified because now ex slaves can come to the slave masters country on the news.
https://www.youtube.com/watch?v=G8SZpv3jROo&feature=youtu.be&t=6m0s



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My favourite rhetorical device to employ against people with abhorrent opinions is -
"Shut the fuck up, you're talking out of your arse, you complete wanker." Often accompanied with an appropriate hand gesture.