And the response (in part) from that thread:
I don't believe that population density causes statism (for every statist measure arising to deal with "spillover effects," there is a better market measure - population density should correlate with greater libertarianism, but the fact that it doesn't is an interesting topic for study)
It is really quite simple, in cities there are more people, so there are more voluntary transactions and associations between those people, which leads to a more diversified and efficient society; this has been, and always will be the attraction of cities.
The problem is, if forced government action is injected into each and every set of voluntary transactions, they become less voluntary and the parties involved become less motivated to persue voluntary solutions: government power increases while society becomes less efficient.
If liberty is instilled in the minds and hearts of people, they take more responsibility for the way they conduct their lives and how they relate with others. People can be just as addicted to trying to control others, no matter if they live in the city or out in a Unabomber-shack in rural Montana. There is just less frequent transactions and urgency to solve "spill-over" effects in rural areas and the statists have less power by default.
The key is, there is always total government
, as Varrin was pointing out in his previous message here. It just depends on how much of that government a society delegates to others, and whether it is done voluntarily or by force. A free city is not an enigma!
Just a little hard to come by right now under the current paradigm of government by force.