What, sir, would the people of this earth be without woman? They would be scarce, sir. Mighty scarce.
Mark Twain (1835-1910) American writer [pseud. of Samuel Clemens]
“Women, a Eulogy of the Fair Sex,” Speech at the Correspondents Club, Washington, DC (11 Jan 1868)
(Source)
The speech (responding to a toast) was printed on 13 January in the Washington Star. The last sentence (or, in some cases, "Almighty scarce") was apparently added later in Twain's published speeches.
Variant: "What would men be without women? Scarce, sir, mighty scarce."