“In all ages, whatever the form and name of government, be it monarchy, republic, or democracy, an oligarchy lurks behind the façade….”

On New Democracy (1940)
Original: (zh-CN) 国体——各革命阶级联合专政。政体——民主集中制。这就是新民主主义的政治，这就是新民主主义的共和国，这就是抗日统一战线的共和国，这就是三大政策的新三民主义的共和国，这就是名副其实的中华民国。我们现在虽有中华民国之名，尚无中华民国之实，循名责实，这就是今天的工作。

Section III, "Of Civil Liberty"
Essay on the First Principles of Government, 2nd Edition (1771)

26 June 1787 per page 105 of "The Debates, Resolutions, and Other Proceedings, in Convention, on the Adoption of the Federal Constitution: Supplementary to the state Conventions" by Johnathan Elliot, published 1830 https://books.google.ca/books?id=-gtAAAAAYAAJ&pg=RA1-PA105
Debates of the Federal Convention (1787)

What I Believe (1938)
Context: Democracy is not a beloved Republic really, and never will be. But it is less hateful than other contemporary forms of government, and to that extent it deserves our support. It does start from the assumption that the individual is important, and that all types are needed to make a civilization. It does not divide its citizens into the bossers and the bossed — as an efficiency-regime tends to do. The people I admire most are those who are sensitive and want to create something or discover something, and do not see life in terms of power, and such people get more of a chance under a democracy than elsewhere. They found religions, great or small, or they produce literature and art, or they do disinterested scientific research, or they may be what is called "ordinary people", who are creative in their private lives, bring up their children decently, for instance, or help their neighbours. All these people need to express themselves; they cannot do so unless society allows them liberty to do so, and the society which allows them most liberty is a democracy.

Speech in the House of Commons (11 November 1947), published in 206–07 The Official Report, House of Commons (5th Series), 11 November 1947, vol. 444, cc. http://hansard.millbanksystems.com/commons/1947/nov/11/parliament-bill#column_206
Post-war years (1945–1955)
Variant: Democracy is the worst form of government, except all the others that have been tried.
Context: Many forms of Government have been tried and will be tried in this world of sin and woe. No one pretends that democracy is perfect or all-wise. Indeed, it has been said that democracy is the worst form of government except all those other forms that have been tried from time to time.

As quoted in Freedom: A New Analysis (1954) by Maurice William Cranston, p. 112

Source: Anti-Machiavel, Chapter IX

Frame of Government (1682)
Context: I know what is said by the several admirers of monarchy, aristocracy and democracy, which are the rule of one, a few, and many, and are the three common ideas of government, when men discourse on the subject. But I chuse to solve the controversy with this small distinction, and it belongs to all three: Any government is free to the people under it (whatever be the frame) where the law rules, and the people are a party to those laws, and more than this is tyranny, oligarchy, or confusion.