In this 6 1/2 minute video, CGP Gray explains how the mathematics of a one person/one vote system inevitably leads to a two-party system that pleases almost no one.
Also from CGP Gray:
- A Case Against the Penny
- What the Bleep is the United Kingdom?!
- The Economics of Royalty
- The Social Construction of the Continents
- A History and Account of Daylight Savings
Comments 18
Justin Nelson — November 4, 2012
"One person one vote" and first-past-the-post are not synonymous. In a lot of other electoral systems (STV, proportional representation) there is a principle of one person, one vote.
Sam Loy — November 4, 2012
Nonsense. Everyone knows Owl rules.
seanpodge — November 5, 2012
One person one vote is not the problem! It's First Past The Post and single member electorates that are the issues when it comes to the cause of two party systems/duopolies. Not sure how anyone can seriously argue against one vote one value while also claiming to believe in democracy.
Skalchemist — November 5, 2012
I agree with the general sentiment that first past the post leads to inevitable problems, especially the basic premise that leads paradoxically to a situation where the majority is almost never happy with the outcome.
However, it is objectively not true that first past the post leads to a two party system. Canada is the obvious exception, with four major parties. There are two parties that would be the normal two parties in many other countries (Conservatives and Liberals), one party that exists due to regional concerns that trump the basic left/right spectrum (Parti Quebecois), and one party that exists due to, as far as this American expatriate in Canada can tell, an accident of history caused by some VERY hard feelings (the NDP).
This leads me to conclude that two parties are inevitable only if the preponderance of the issues that drive how people vote can be arranged roughly on a single dimension. If there are two or more dimensions involved (regional animosities, historical grudges, etc.), two parties are not inevitable.
Die Tücken des Zweiparteiensystems « kult|prok — November 5, 2012
[...] Im Gegensatz zu Karl Poppers Gründen, die für ein Zweiparteiensystem sprechen sollen, habe ich noch immer meine Bedenken, das dies auch nur entfernt Vorzüge hat. Nur stütze ich mich dabei auf ein etwas vorgebildetes Bauchgefühl und krumme Analogien. Dass es anders geht, zeigt C. G. B. Grey in The Problems with First Past the Post Voting Explained [via]: [...]
decius — November 5, 2012
Note that there proof that there is no voting system that meets four specific criteria that is capable of handling three or more options.
In general, those criteria are:
No one individual controls the entire election.
It must always be able to rank every option, and those rankings must be deterministic on the voting.
The preference of the people for owl over tiger and gorilla must not change the relative ranking of tiger and gorilla. (This is the major problem with FPTP) (Independence of irrelevant alternatives)
If everyone prefers one option to another, the preferred option must win.
This doesn't hinge on the difficulty of breaking ties, either: The proof is that there is somebody who can manipulate any system with the last three qualities to control the entire decision.