groundbreaker vs guiding light

groundbreaker

noun
  • First person to do, make or fight for something. A pioneer; a seminal person. 

guiding light

noun
  • A person who has a profound influence on others and is a source of inspiration. 

  • That which provides guidance in times of uncertainty. 

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