initiatory vs syllogistic

initiatory

adj
  • Of or pertaining to initiation 

  • inceptive, initial, inaugural or introductory 

noun
  • An introductory act or rite. 

syllogistic

adj
  • Of or pertaining to a syllogism. 

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