babble vs talk to oneself

babble

verb
  • To utter in an indistinct or incoherent way; to repeat words or sounds in a childish way without understanding. 

  • To reveal; to give away (a secret). 

  • To utter words indistinctly or unintelligibly; to utter inarticulate sounds 

  • To talk incoherently; to utter meaningless words. 

  • To talk too much; to chatter; to prattle. 

  • To make a continuous murmuring noise, like shallow water running over stones. 

noun
  • A sound like that of water gently flowing around obstructions. 

  • Idle talk; senseless prattle 

  • Inarticulate speech; constant or confused murmur. 

talk to oneself

verb
  • To say one's thoughts aloud, particularly while also not conversing with anyone else. 

How often have the words babble and talk to oneself occurred in a corpus of books? (source: Google Ngram Viewer )