When citizens are relatively equal, politics has tended to be fairly democratic. When a few individuals hold enormous amounts of wealth, democracy suffers. The reason for this pattern is simple. Through campaign contributions, lobbying, influence over public discourse, and other means, wealth can be translated into political power. When wealth is highly concentrated — that is, when a few individuals have enormous amounts of money — political power tends to be highly concentrated, too. The wealthy few tend to rule. Average citizens lose political power. Democracy declines.
Benjamin I. Page (b. 1940) American political scientist, academic, researcher
Democracy in America?: What Has Gone Wrong and What We Can Do About It, Part 1, ch. 2 (2017) [with Martin Gilens]
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