The difference between labor and land is that land is conserved while labor is subject to erasure by the second law of thermodynamics. That is one quick way to differentiate between the two. You may have added improvements to land, and so you validly own the labor in those improvements, but all those decay with time. The space however remains.
Hence
to say you own the space, because you found it and put a fence around
it at some point in time is bogus. You were free to use it, but when
there's no more space for others and people start becoming landless,
then principles of liberty (in contrast to mere "freedom") have to kick
in.
Rich
people have no more rights to Nature than poor people, and people who
are "there first" have no more rights to Nature than people who come
later. Life isn't fair, and we all have different capabilities, but
Nature was given to us with no partiality.
"If
we are all here by the equal permission of the Creator, we are all here
with an equal title to the enjoyment of his bounty -- with an equal
right to the use of all that nature so impartially offers.1 This is a
right which is natural and inalienable; it is a right which vests in
every human being as he enters the world, and which during his
continuance in the world can be limited only by the equal rights of
others. There is in nature no such thing as a fee simple in land. There
is on earth no power which can rightfully make a grant of exclusive
ownership in land. If all existing men were to unite to grant away their
equal rights, they could not grant away the right of those who follow
them. For what are we but tenants for a day? Have we made the earth,
that we should determine the rights of those who after us shall tenant
it in their turn? The Almighty, who created the earth for man and man
for the earth, has entailed it upon all the generations of the children
of men by a decree written upon the constitution of all things -- a
decree which no human action can bar and no prescription determine."
Henry George - Progress and Poverty.
