Mattheus has a response here. He's wrong, of course, and fails to quote precisely the passages from my post and Gene's post that would answer his questions - but he gives it a shot :)
Roderick Long - I presume completely independently - has a post on libertarian claims about property here.
I also want to share this great passage from John Dewey's Liberty and Social Control (1935):
"Demand for retention of powers already possessed on the part of a particular group means, therefore, that other individuals and groups shall continue to possess only the capacities in and for activity which they already possess. Demand for increased power at one point means demands for change in the distribution of powers, that is, for less power somewhere else. You cannot discuss or measure the liberty of one individual or group of individuals without measuring the difference of levels.
In the third place, this relativity of liberty to the existing distribution of powers of action, while meaning that there is no such thing as absolute liberty, also necessarily means that wherever there is liberty at one place there is restraint at some other place. The system of liberties that exists at any time is always the system of restraints or controls that exists at that time. No one can do anything except in relation to what others can do and cannot do.
These points are general. But they cannot be dismissed as mere abstractions. For when they are applied either in idea or in action they mean that liberty is always a social question, not an individual one. For the liberties that any individual actually has depends upon the distribution of powers or liberties that exists, and this distribution is identical with actual social arrangements, legal and political -- and, at the present time, economic, in a peculiarly important way.
Return now to the fact that historically the great movements for human liberation have always been movements to change institutions and not to preserve them intact. It follows from what has been said that there have been movements to bring about a changed distribution of power to do - and power to think and to express thought is a power to do - such that there would be a more balanced, a more equal, even, and equitable system of human liberties.
The present movement for social control of industry, money and credit, is simply a part of this endless human struggle. The present attempt to define liberty in terms of the existing distribution of liberty is an attempt to maintain the existing system of control of power, of social restraints and regimentations."