grey matter vs nous

grey matter

noun
  • Brains; a person's ability to think. 

  • A collection of cell bodies and (usually) dendritic connections, in contrast to white matter. 

  • Literal brains as a general substance. 

nous

noun
  • The mind or intellect, reason, both rational and emotional 

  • In Neoplatonism, the divine reason, regarded as first divine emanation. 

  • The "mind-set" of a society, culture, or group -- as in Homer's use in the third verse of the Odyssey. 

  • Common sense; practical intelligence. 

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