Dunkirk spirit vs stoicism

Dunkirk spirit

noun
  • The spirit of the British public pulling together to overcome times of adversity. 

stoicism

noun
  • A school of philosophy popularized during the Roman Empire that emphasized reason as a means of understanding the natural state of things, or logos, and as a means of freeing oneself from emotional distress. 

  • A real or pretended indifference to pleasure or pain; insensibility; impassiveness. 

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