“A government is never more dangerous than when embarking on a self-defeating or downright suicidal course.”

Source: The Autobiography of Calvin Coolidge (1929)

Source: A Distant Mirror (1978), p. 487

1850s, Speech at Peoria, Illinois (1854)
Context: "Fools rush in where angels fear to tread." At the hazard of being thought one of the fools of this quotation, I meet that argument — I rush in — I take that bull by the horns. I trust I understand and truly estimate the right of self-government. My faith in the proposition that each man should do precisely as he pleases with all which is exclusively his own lies at the foundation of the sense of justice there is in me. I extend the principle to communities of men as well as to individuals. I so extend it because it is politically wise, as well as naturally just: politically wise in saving us from broils about matters which do not concern us. Here, or at Washington, I would not trouble myself with the oyster laws of Virginia, or the cranberry laws of Indiana. The doctrine of self-government is right, — absolutely and eternally right, — but it has no just application as here attempted. Or perhaps I should rather say that whether it has such application depends upon whether a negro is not or is a man. If he is not a man, in that case he who is a man may as a matter of self-government do just what he pleases with him.
But if the negro is a man, is it not to that extent a total destruction of self-government to say that he too shall not govern himself. When the white man governs himself, that is self-government; but when he governs himself and also governs another man, that is more than self-government — that is despotism. If the negro is a man, why then my ancient faith teaches me that "all men are created equal," and that there can be no moral right in connection with one man's making a slave of another.

[199804141540.IAA05247@wall.org, 1998]
Usenet postings, 1998

Speech on Military Preparedness http://books.google.com/books?id=-rIqAAAAYAAJ&pg=RA9-PA11&dq=PITTSBURGH, Pittsburgh (29 January 1916)<!--PWW 36:28-33-->
1910s
Context: Do you never stop to reflect just what it is that America stands for? If she stands for one thing more than another, it is for the sovereignty of self-governing peoples, and her example, her assistance, her encouragement, has thrilled two continents in this Western World with all the fine impulses which have built up human liberty on both sides of the water.

Nos lois civiles ne seront jamais assez souples pour s'adapter à l'immense et fluide variété des faits. Elles changent moins vite que les moeurs; dangereuses quand elles retardent sur celles-ci, elles le sont davantage quand elles se mêlent de les précéder.
Source: Memoirs of Hadrian (1951), p. 113

Source: Vamps and Tramps (1994), "No Law in the Arena: A Pagan Theory of Sexuality", p. 51
Context: Campus speech codes, that folly of the navel-gazing left, have increased the appeal of the right. Ideas must confront ideas. When hurt feelings and bruised egos are more important than the unfettered life of the mind, the universities have committed suicide.

Widely attributed to Campbell-Bannerman since at least 1910 https://api.parliament.uk/historic-hansard/commons/1910/jul/12/parliamentary-franchise-women-bill-1. However it appears unattributed earlier https://books.google.co.uk/books?id=rIFPAAAAYAAJ&focus=searchwithinvolume&q=%22self-government+is+better%22, and the concept pre-dates https://books.google.co.uk/books?id=lFI3AAAAMAAJ&pg=PA403&lpg=PA403&dq=%22your+public-spirited+advocates+of+good+government,+I+do+find+sneering+upon+the+self-government+of+the+Christian%22 Campbell-Bannerman.
Compare Gandhi: "Good government is no substitute for self-government." Young India (2 September 1920), p. 1
Attributed

Source: Motivation and Personality (1954), p. 123.