The nobleman can never have a Friend among his retainers, nor the king among his subjects.
 Henry David Thoreau, A Week on the Concord and Merrimack Rivers (1849). copy citation

Context

“and perhaps it is more rare between the sexes than between two of the same sex. Friendship is, at any rate, a relation of perfect equality. It cannot well spare any outward sign of equal obligation and advantage. The nobleman can never have a Friend among his retainers, nor the king among his subjects. Not that the parties to it are in all respects equal, but they are equal in all that respects or affects their Friendship. The one’s love is exactly balanced and represented by the other’s. Persons are only the vessels which contain the nectar, and the hydrostatic paradox is the symbol of love’s law.” source