Montesquieu

What I have just said is even more indis­pen­sa­ble in the des­po­tic state. The lord who may at any moment be dis­pos­ses­sed of his lands and his sla­ves is not so deter­mi­ned to pre­serve them.

Peter I, inten­ding to take over Germany and levy his tri­bu­tes in spe­cie, made a very wise rule that is still fol­lo­wed in Russia. The gent­le­man levies the tax on the pea­sants and pays it to the czar. If the num­ber of pea­sants decli­nes, he pays just as much ; if the num­ber increa­ses, he does not pay more : he the­re­fore has an inte­rest in not haras­sing his pea­sants.