Adam Ferguson notes that “implicit submission to any leader, or the uncontrouled exercise of any power” leads to a form of military government and ultimately despotism (1767)

Found in An Essay on the History of Civil Society
In SECTION VI. “Of the Progress and Termination of Despotism” of his pioneering work of “philosophical history,” Adam Ferguson reflects on how free and prosperous nations might step-by-step degenerate into despotism:
We have already observed, that where men are remiss or corrupted, the virtue of their leaders, or the good intention of their magistrates, will not always secure them in the possession of political freedom. Implicit submission to any leader, or the uncontrouled exercise of any power, even when it is intended to operate for the good of mankind, may frequently end in the subversion of legal establishments. This fatal revolution, by whatever means it is accomplished, terminates in military government; and this, though the simplest of all governments, is rendered complete by degrees.
A common theme in many 18th century authors wax that of decline, corruption, and the descent into despotism. This can be clearly seen in Edward Gibbon’s Decline and fall of the Roman Empire (1776) and here in Adam Ferguson’s book. The image Ferguson uses, of decline and loss of liberty by “slow, and almost imperceptible steps” reminds one of the story of the frog in the pot of boiling water. It does not know when to jump out of the pot until it is too late.