It is impossible to conceive of the idea of property arising from anything but manual labour, for it is not clear what man can add, beyond his own labour, in order to appropriate things he has not made.
Gist of Idea
What else could propert arise from, but the labour people add to it?
Jean-Jacques Rousseau (Discourse on the Origin of Inequality , Part II)
A thorough endorsement of Locke's labour theory of value. It is not clear to me why you have to 'add' something in order to achieve ownership. Don't you own firewood just by picking it up? Golfers give ownership of a lost ball to the first one to see it.
Rousseau,Jean-Jacques: 'The Basic Political Writings', ed/tr. Cress,Donald A. [Hackett 1987], p.66
Idea 19781 Land cultivation led to a general right of ownership, administered justly [Rousseau]