perception vs thoughtlessness

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 

thoughtlessness

noun
  • heedless disregard for the consequences of one's actions 

  • disregard for other's feelings 

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