credulous vs mistrustful

credulous

adj
  • Believed too readily. 

  • Excessively ready to believe things; gullible. 

mistrustful

adj
  • Having a suspicion, imagining or supposing (that something undesirable is the case). 

  • Expressing or showing a lack of trust. 

  • Having mistrust, lacking trust (in someone or something). 

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