moving force vs quintessence

moving force

quintessence

verb
  • To reduce to its purest and most concentrated essence. 

noun
  • A thing that is the most perfect example of its type; the most perfect embodiment of something; epitome, prototype. 

  • A pure substance. 

  • The fifth alchemical element, or essence, after earth, air, fire, and water that fills the universe beyond the terrestrial sphere. 

  • The essence of a thing in its purest and most concentrated form. 

  • A hypothetical form of dark energy postulated to explain observations of an accelerating universe. 

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