discourse vs occasion

discourse

noun
  • Any rational expression, reason. 

  • Expression in words, either speech or writing. 

  • A formal lengthy exposition of some subject, either spoken or written. 

  • An institutionalized way of thinking, a social boundary defining what can be said about a specific topic (after Michel Foucault). 

verb
  • To exercise reason; to employ the mind in judging and inferring; to reason. 

  • To engage in discussion or conversation; to converse. 

  • To write or speak formally and at length. 

occasion

noun
  • A reason or excuse; a motive; a persuasion. 

  • Need; requirement, necessity. 

  • The time when something happens. 

  • Something which causes something else; a cause. 

  • A special event or function. 

  • A particular happening; an instance or time when something occurred. 

  • An occurrence or state of affairs which causes some event or reaction; a motive or reason. 

  • A favorable opportunity; a convenient or timely chance. 

verb
  • To cause; to produce; to induce 

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