“My lord and Dr Johnson disputed a little, whether the savage or the London shopkeeper had the best existence; his lordship, as usual, preferring the savage.”
The lord was James Burnett, Lord Monboddo, (21 August 1773)
See similar debate in Angel.
The Journal of a Tour to the Hebrides with Samuel Johnson, LL.D. (1785)
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James Boswell 23
Scottish lawyer, diarist and author 1740–1795Related quotes

“Eyes exist in the savage state.”
L'œil existe à l'état sauvage.
Le Surréalisme et la Peinture, (1926) Andre Breton

Source: 1930s-1951, Philosophical Occasions 1912-1951 (1993), Ch. 7 : Remarks on Frazer's Golden Bough, p. 131
Context: Frazer is much more savage than most of his savages, for they are not as far removed from the understanding of spiritual matter as a twentieth-century Englishman. His explanations of primitive practices are much cruder than the meaning of these practices themselves.

Boule de Suif (1880)
Context: The same thing happens whenever the established order of things is upset, when security no longer exists, when all those rights usually protected by the law of man or of Nature are at the mercy of unreasoning, savage force. The earthquake crushing a whole nation under falling roofs; the flood let loose, and engulfing in its swirling depths the corpses of drowned peasants, along with dead oxen and beams torn from shattered houses; or the army, covered with glory, murdering those who defend themselves, making prisoners of the rest, pillaging in the name of the Sword, and giving thanks to God to the thunder of cannon — all these are appalling scourges, which destroy all belief in eternal justice, all that confidence we have been taught to feel in the protection of Heaven and the reason of man.

“Don't be surprised if I behave like a savage. I am a savage.”
http://www.usfca.edu/~southerr/boxing/fury.html
On himself
“Life Among the Savages is a disrespectful memoir of my children.”
Stanley J. Kunitz and Howard Harcraft's Twentieth Century Authors (1954)

The Artist and the Shopkeeper
The Note-Books of Samuel Butler (1912), Part XI - Cash and Credit