There’s bad folk everywhere, and what’s far worse, weak ones.

Robert Louis Stevenson (1850–1894) Scottish essayist, novelist, poet

Novel (1886), Kidnapped, ch. 21 “The Flight in the Heather: The Heugh of Corrynakiegh” [Alan]
    (Source)

Expressing concern about being seen, given there's a price on his head.

This chapter was originally published in Young Folks Paper, Vol. 28, No. 813 (1886-06-26).