marbles vs rationality

marbles

noun
  • Sanity. 

  • Bits of rolled-up rubber shed by the tires of race cars that accumulate at the edges of the track, especially at the corners. 

  • Any of several children's games played with small balls (made of marble or more commonly glass). 

rationality

noun
  • The quality or state of being rational; due exercise of reason; reasonableness. 

  • Objective consideration. 

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