Dawson, R.M. (1958) William Lyon Mackenzie King.
Vol. 1: A Political Biography. 1874–1923
Page 148

You need to read the entire paragraph (scanned at right)
from the beginning to appreciate the pun at the last line.

Why was Mackenzie King singled out for so many divergent assignments? The answer is probably twofold: his recognized energy and ability, and the scarcity of suitable personnel. His unusually wide interests* were well supported by superior intelligence, confidence, forcefulness, native shrewdness, and a knack of producing results. Moreover, his knowledge extended to topics familiar to very few in the civil service, which underwent its first genuine reform only in 1908, all offices hitherto having been filled largely through patronage. The earlier system had produced occasional good appointments (King's selection by Mulock had been of this kind), but it had also led to many poor ones. The number of well-trained men was consequently small, and specialists could be found in only a few fields. Thus when Laurier wrote King in November of 1908 regarding his attendance at the international opium conference (see p. 192) he alluded to the fact that King had "made a special study of the opium problem in this country, and of other questions arising out of our relations with the Far East,"⁴⁵ though even the most charitable could never have described King as an expert. The truth was that the Canadian service did not contain anyone qualified to challenge King's knowledge, such as it was, on the subject of opium, although doubtless there were a number of immigration officials who had some familiarity with Far Eastern relations. In the country of the blind, the one-eyed man was king.