Proportional representation is good for liberalism

With a first-past-the-post voting system voters generally take into account how they expect other people to vote. This is called tactical voting and the reason for this is that if there is only one winner then we are wasting our vote if we vote for a minority candidate. It only makes sense to vote for a candidate we know to be popular and who has a chance of winning. This means that minority concerns are - or can be - ignored by the fptp system. A better system is one where voters are able to vote in a 'naive' sense... that is to say that they can simply choose their favourite candidate without being concerned that their vote would have more influence if they voted for a more favoured candidate. Tactical voting reduces the power of democracy which means it encourages tyranny and the expansion of the state. If there is a two-party system then always one of these parties will be of the left and because voters are generally unsympathetic to the state it is the left who will generally do better. Left-wing voters are more inclined to support the government and so they have less of a disinclination to vote for the dominant party. Voters on the 'right' do not like government and so do not like voting for the big party of government. A proportional system makes it very difficult for the left to do well because if people vote for the politician which most closely matches themselves this will lead to a splintering of the political establishment because people have disparate concerns. So then proportional representation leads to a fracturing of the political system which diminishes the power of the state. If the voting system is more proportional this is bad for the large political parties and so it is good for the voter. What is bad for the large parties is bad for the government (and socialism) and so pr will lead to more liberalism.

First past the post advocates are not arrogant

We might think that it is arrogant for a person to advocate the use of first past the post because they are making the assumption that to choose from only two parties is adequate. But in reality their mistake is not one of arrogance but rather one of insanity. The difference is that people who advocate or defend first past the post are doing so not because they are defending its virtues but instead because they fail to see what is wrong with it... they fail to see the liberal advantages of a more proportional system.

They fail to see that there is more government and more (unwanted) socialism if voters are denied full democracy. It is not an error of arrogance to defend first past the post but ignorance or insanity.

To use first past the post should be illegal

Socialism is not necessarily caused by democracy... in fact there are good arguments to show that if there is less democracy this will lead to more socialism. With less democracy (as with fptp) the government must to some degree guess the intentions of the voting public. Which will usually lead to more government because the state is inclined to enlarge and favour itself. With pr we know precisely what the public want and don't want. It is very likely that with a more transparent and open voting system there will be less socialism (and certainly less bad socialism) because the public will realise it is to their detriment. Governments often use the concept of socialism merely to enrich themselves and with more democracy this is not possible. Democracy prevents socialism otherwise there would be no reason to have elections to begin with. If democracy doesn't lead to the diminution of the state (by allowing the people to choose whom leads) then it would serve no purpose. Democracy enables the people to choose the leaders which means there is less consensus around established state leaders and more anarchy. No government should be allowed to form which does not use the most transparent and open form of democracy possible. It should be illegal for the state to use fptp.

Anarchists do not prefer fptp to pr

It is consistent for anarchists to prefer a proportional voting system to first past the post. The reason for this is that with pr voters have more choice and since democracy is to protect the people from the government this means less government. With fptp we can be almost certain that a two-party system will emerge... this means that fptp is helpful to those parties only and there is no reason for someone who supports neither of the two main parties to be supportive of fptp. Fptp favours the two main parties and - in a closed system - this means that it is detrimental to the rest of the public. Supporters of the two main parties benefit from fptp but no one else. Anarchists (who support neither of the main parties) must prefer pr because at least they can choose a party which is closer to their beliefs. There is no reason to think that an anarchist is served by less democracy and less choice. Democracy is bad for the state. Anarchists do not like the state and so anarchists like democracy. What is bad for the state is good for anarchists and so anarchists like democracy and prefer pr to fptp because it is more democratic. Someone who prefers fptp to pr is not an anarchist.

We own ourselves and we own our own vote

The reason to have laws is to improve the political environment for everyone involved. Laws are rules which concern the range of permitted behaviours between people. They are designed to improve life and as such they are an objectively good thing. Since laws come only from the government then we can simply deduce that the government is an objectively good thing. Something is not supported in law if (when applied globally to everyone) it does not result in an improved society. A typical example of something which is rejected in law would be slavery (the ownership of people)... it is not possible (permissible) in law to own people because this clearly does not serve the wider public good. A second example of something which is not allowed would be (outright) landownership. Whilst this issue is perhaps more nuanced and complicated than the ownership of people we can still see how landownership might not be conducive to the public good. So both slavery and anti-Georgism are rejected in law. (So we cannot own people and we cannot own land.) A third such example of something that we cannot own would be the votes of another person. We can neither purchase or otherwise obtain the vote of another person since this is not helpful to the health of the society as a whole. This means that all (general) elections must be conducted in such a way that voters are able to vote for (or reject) whom they like without consideration to tactical concerns. If there is not proportional representation or something like it then their votes and their democratic privileges have been stolen by the governing elite. This is theft of the civic rights of the people. We cannot own the votes of another person and for that reason first-past-the-post is an invalid approach. We own ourselves and we own only our own vote which means that as a government we cannot implement fptp. It is good to have property rights and a system of laws and so it is good to have a government. First past the post is a threat to the government because it doesn't respect the right of the people to own their own vote. Since fptp is a threat to the government it is anarchistic and a bad thing. We own our own vote and so we can use only a fair and proportional voting system.