“In the country of the blind the one-eyed man is king.”
Adagia (first published 1500, with numerous expanded editions through 1536), III, IV, 96
Also in the same passage of the Adagia is a variant: Inter caecos regnat strabus (Among the blind, the squinter rules).
Original
In regione caecorum rex est luscus.
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Desiderius Erasmus 36
Dutch Renaissance humanist, Catholic priest, and theologian 1466–1536Related quotes

“In the land of the blind the one-eyed man is king.”
In terra di ciechi chi vi ha un occhio è signore.
Act III, scene ix
The Mandrake (1524)
Clifford Geertz, Local Knowledge: Further Essays in Interpretive Anthropology (1983) Basic Books, 2000, p. 58.

“Who is king in the world of the blind when there isn't even a one eyed man?”
Source: The Age of Uncertainty (1977), Chapter 6, p. 180
“In the country of the blind the one-eyed man is lucky to escape with his life.”
The Decline and Fall of Science (1976)

Source: The Outsider (1956), Chapter one, The Country of the Blind, referencing a quote by Desiderius Erasmus.
Context: He alone is aware of the truth, and if all men were aware of it, there would be an end of life. In the country of the blind, the one-eyed man is king. But his kingship is kingship over nothing. It brings no powers and privileges, only loss of faith and exhaustion of the power to act. Its world is a world without values.

“In the land of the blind, the one-eyed man is stoned to death.”

We are a little bit that way.
On India's performance amid the 2015 world economy slow down, as quoted in " India 'one-eyed' king in land of blind, says Rajan http://www.business-standard.com/article/finance/india-one-eyed-king-in-land-of-blind-says-rajan-116041600663_1.html", Business Standard (16 April 2016)

“In the land of the blind, the one-eyed man will poke out his eye to fit in.”
12 December 2010
Unfit for Mass Consumption (blog entries), 2010