Proportional representation

Proportional representation (PR) is a goal of some methods of distributing seats in legislatures, mostly outside the Anglosphere. It is very popular in Scandinavia, as well as Germanic or Slavic countries. Because the methods claim to be fairer than first past the post, it attracted many utopians since the late 19th century, including John Stuart Mill who suggested one method for the UK (the Hare system, now being used in Ireland and Malta).

One particular method that tries to get the best of both systems, is being used in Germany and New Zealand: Mixed member proportional voting.

Representation of Minority Views

 * To Stuart Mill, minorities ought to be represented in Parliament, which the FPTP method does not naturally provide without special redistricting.

Coalition and consensus

 * PR, in theory, easily elects a small party (who needs just a fraction of the votes)
 * It makes coalition governments the norm rather than the exception.

Less Polarization

 * Since there are multiple parties, they are less likely to attack each other viciously they might need to form a coalition later.
 * Instead of promoting bitter, toe-to-toe campaigns, coalitions make political life calmer. As the parties are smaller under such a system, they do not need to endlessly flip-flop between two political extremes to get a majority; they do not seek one.

Ways to limit party fragmentation

 * few-member constituencies (increasing the fraction), example: Spain, Ireland, Australia
 * threshold, example: Turkey (10%), Germany (5%), New Zealand (5%)

Lack of governability
A fragmented vote and the necessity of coalitions can produce rapid turnover of cabinets (e.g. the 61 Italian cabinets 1946-'94 or the 21 French Prime Ministers during the 1946-'58). However, the necessity of making legislation "proof" against such changes can also result in broad consensus bargains between cabinet and opposition parties. In extreme cases, government formation can be completely impossible if minority governments are not allowed. For example, no government formed after the Israeli elections of April 2019 or September 2019, and the government that formed following the March 2020 election lasted only a few months. The result of all of this was an extended political stalemate that had to be resolved by repeatedly holding new elections (Israel held a fourth election over the two year period in March 2021). Whether fragmentation of the vote produces weak governments depends on the distribution of power between the legislature and the executive, the "elasticity" of the vote (whether voters tend to vote for the same parties in every election), whether the legislature tends towards consensus-building or adversarial partisanship, and the degree to which parties tend to switch sides between supporting the opposition and the government as well as whether politicians go "party shopping" after an election (leaving the party for which they were elected). It’s also worth noting that just because a system uses fixed election cycles and a FPTP system, governability may not be particularly good either, such as evinced by the frequently deadlocked US Congress.

1986 French experiment
In 1986 France's socialist government experimented a switch to PR, as a reward to its leftists allies for helping their election in 1981, and a try to minimize a foreseen defeat. Although the results did what the system was supposed to, it generated an outcry for:
 * allowing representation for the extreme nationalist Front National,
 * depriving several established (right-wing) representatives of their usual seat.

The moral panic about the growth of the Front National was augmented by talks of the socialist president Francois Mitterand being pleased, because it led to division of the right. The new right-wing government quickly shelved the system. Not that it prevented the Front National from growing larger, as shown by the fully proportional European election, up to snatching the second turn of the presidential election from the socialists in 2002 - forcing most left-wing voters to grudgingly plebiscite the right-wing candidate Jacques Chirac. Or the next president, Nicolas Sarkozy, to include fearmongering and populist stances in his election program. Breaking the thermometer has rarely healed a fever.