delusion vs perception

delusion

noun
  • That which is falsely or delusively believed or propagated; false belief; error in belief. 

  • A false belief that is resistant to confrontation with actual facts. 

  • A fixed, false belief, that will not change, despite evidence to the contrary. 

  • The state of being deluded or misled, or process of deluding somebody. 

perception

noun
  • That which is detected by the five senses; not necessarily understood (imagine looking through fog, trying to understand if you see a small dog or a cat); also that which is detected within consciousness as a thought, intuition, deduction, etc. 

  • Vision (ability) 

  • Conscious understanding of something. 

  • The organisation, identification and interpretation of sensory information. 

  • Acuity 

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