John Locke, a key Enlightenment philosopher, articulated a very influential theory of property in his "Second Treatise of Government.
" This is often called the Labor Theory of Property.
He argued that while the Earth and its resources are initially common to all humanity, every person owns their own body and, by extension, their own labor.
When an individual "mixes his labor" with a natural resource (e.
g.
, by picking an apple from a tree or cultivating a piece of land), that labor becomes part of the object, removing it from the common state and making it their private property.