moderation vs restraint

moderation

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

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

  • The process of moderating a discussion 

restraint

noun
  • control or caution; reserve 

  • something that restrains, ties, fastens or secures 

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