phlegm vs self-possession

phlegm

noun
  • Calmness of temperament, composure; also seen negatively, sluggishness, indifference. 

  • One of the four humors making up the body in ancient and mediaeval medicine; said to be cold and moist, and often identified with mucus. 

  • Viscid mucus produced by the body, later especially mucus expelled from the bronchial passages by coughing. 

  • A watery distillation, especially one obtained from plant matter; an aqueous solution. 

self-possession

noun
  • calmness and composure, especially when under stress 

  • confidence in one's own powers 

How often have the words phlegm and self-possession occurred in a corpus of books? (source: Google Ngram Viewer )