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This is one of the more famous results in political science: Duverger's Law. It's normally phrased as "in a first past the post system, the number of effective
by pmyteh 7y ago
This is one of the more famous results in political science: Duverger's Law. It's normally phrased as "in a first past the post system, the number of effective parties tends towards two".
It's... a useful model. It turns out not to work in practice everywhere, though, as there are complicating features with geography and ideology that tend to add parties. Canada, for example, has 2 and a half effective parties (Liberal, Conservative, NDP) in general, and more in Québec. The UK also has two and a half (Con, Lab, Lib Dem) plus powerful Scottish and Welsh nationalist parties, plus an entirely different party system in Northern Ireland. So 'tends towards' is going a lot of work.
- hippich 7y agoI think we start seeing that in the U.S. with younger congress members not being satisfied with lumping them all together with more traditional politicians. Who knows, maybe we will get that here too. EDIT: Also, if the system tries to equalize at two parties, why we do not see a similar process inside parties themselves?
- pmyteh 7y agoIf the parties have stable factions and their internal elections are FPTP, then sure. The two right-wing factions of the British Labour party just rolled over the party's left-wing by running a joint slate of candidates while the left slates split the vote. Having said that, electoral politics within parties doesn't tend to be as important as other things: bureaucratic control of the party machinery, for example.