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.)
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Usually quoted with just the last two sentences, and misattributed directly to Bell.