From Chapter 9, Coercion and the State, of Hayek’s crucial Constitution of Liberty:
“The recognition of private or several property is thus an essential condition for the prevention of coercion, though by no means the only one. We are rarely in a position to carry out a coherent plan of action unless we are certain of our exclusive control of some material objects; and where we do not control them, it is necessary that we know who does if we are to collaborate with others. The recognition of property is clearly the first step in the delimitation of the private sphere which protects us against coercion; and it has long been recognized that “a people averse to the institution of private property is without the first element of freedom” and that “nobody is at liberty to attack several property and to say at the same time that he values civilization. The history of the two cannot be disentangled.” Modern anthropology confirms the fact that “private property appears very definitely on primitive levels” and that “the roots of property as a legal principle which determines the physical relationship between man and his environmental setting, natural or artificial, are the very prerequisite of any ordered action in the cultural sense.” “
The essence of the philosophy of liberty is just as much about what we cannot own as what we can own. I own my paycheck, I do not have a right to own any part of yours. I own the results of my voluntary transactions with others, I have no right to the results of voluntary transactions of which I had no part. Liberty is the defense of voluntary transactions, and the subsequent defense of the property that has resulted from those voluntary acts.