Diderot
"What form of wealth could belong to a man, if not the work of the mind...if not his own thoughts...the most precious part of himself, that will never perish, that will imortalize him? What comparison could there be between a man, the very substance of a man, his soul, and a field, a tree, a vine, that nature has offered in the beginning equally to all, and which the individual has only appropriated through cultivating it?"