Full Idea
Under despotism, the law is nothing more than the will of the ruler. Even if the despot were wise, how could a magistrate follow a will unknown to him? He has no choice but to follow his own.
Gist of Idea
The will of a despot is an enigma, so magistrates can only follow their own will
Source
Baron de Montesquieu (The Spirit of the Laws (rev. 1757) [1748], 05.16)
Book Reference
Montesquieu,Baron de: 'Selected Political Writings', ed/tr. Richter,Melvin [Hackett 1990], p.158