One is reminded of the dialectical definition, by the wry Polish intellectual, of capitalism and communism. Capitalism, it is said, is a system wherein man exploits man. And communism — is vice versa.
Daniel Bell (1919-2011) American sociologist, writer, editor, academic
The End of Ideology, Introduction (1961 ed.)
(Source)
Usually quoted with just the last two sentences, and misattributed directly to Bell.