Sentence:  The moonlight was bright this night; playing the part of a miniature sun as it reflected off the white faces of the Caucasian troops, but failing to reveal those of the darker <WSD>persuasion</WSD>. "One thing, Charlie can see them better than he can see me." 
Meaning of the word marked with <WSD> tags:  Another personal, animal or inanimate trait that is not (very) liable to be changed by persuasion, such as sex, gender, ethnicity, origin, profession or nature.