Duopoly is a property of FPP, except where there are big regional differences (as in Canada). The same two parties alternate in power, rarely if ever needing to form a coalition with someone else. Voting for a third party is equivalent to abstention in terms of consequences, and is best understood as being purely expressive.
Ranked-choice (aka IRV, AV, preferential) provides a smoother path away from duopoly, as we are now seeing in Australia. As the vote for the two major parties declines, minority governments have become increasingly common, without producing any of the ill effects implied by dire phrases like "hung parliament". That's the reform that both the UK and US need.
If I might be so bold, I might suggest that you are both correct, each in a certain sense.
Yes, duopoly is not an essential property of FPP. But for the reasons John notes, any pure FPP system will tend (often very strongly) toward duopoly, unless there are other factors involved, such as large regional differences or ranked-choice voting.
Duopoly is a property of FPP, except where there are big regional differences (as in Canada). The same two parties alternate in power, rarely if ever needing to form a coalition with someone else. Voting for a third party is equivalent to abstention in terms of consequences, and is best understood as being purely expressive.
Ranked-choice (aka IRV, AV, preferential) provides a smoother path away from duopoly, as we are now seeing in Australia. As the vote for the two major parties declines, minority governments have become increasingly common, without producing any of the ill effects implied by dire phrases like "hung parliament". That's the reform that both the UK and US need.
Except that duopoly is not a property of FPP.:)
If I might be so bold, I might suggest that you are both correct, each in a certain sense.
Yes, duopoly is not an essential property of FPP. But for the reasons John notes, any pure FPP system will tend (often very strongly) toward duopoly, unless there are other factors involved, such as large regional differences or ranked-choice voting.