moderation vs tempering

moderation

noun
  • An instance of moderating: bringing something away from extremes, especially in a beneficial way 

  • The state or quality of being moderate; avoidance of extremes 

  • The process of moderating a discussion 

tempering

noun
  • The act by which something is tempered. 

How often have the words moderation and tempering occurred in a corpus of books? (source: Google Ngram Viewer )