Proportional representation is liberal

Democracy is good because it is liberal and the opposite of liberalism is criminality. We know that without an element of authoritarianism there is no crime so liberalism is the opposite of crime, which is always authoritarian. If something is not liberal then it is a crime.

So, as far as politics is concerned, we strive for liberalism. It is clear that democracy is always more liberal than its absence because it gives the people over whom the government seeks to rule, the power to replace their leaders with other ones. Democracy, being liberal, is not criminal and anything which stands in the way of democracy is a crime. We know (from earlier) that if democracy is good then pr is good but we can go further by saying that if democracy is liberal then pr is liberal too. And if something is liberal it is to be valued for not being criminal.

Proportional representation is more liberal than first-past-the-post because it is more democratic and democracy is liberal. To be liberal (in a political sense) is objectively good because the opposite involves authoritarianism and as a consequence possible criminality.