A Storm of Swords: Part 1 Steel and Snow (A Song of Ice and Fire, #3 part 1)

by George R.R. Martin

“A queen must listen to all,” she reminded him. “The highborn and the low, the strong and the weak, the noble and the venal. One voice may speak you false, but in many there is always truth to be found.

I often use a similar concept: "Many opinions bracket the truth"