acknowledge vs recognize

acknowledge

verb
  • To own or recognize in a particular quality, character or relationship; to admit the claims or authority of; to give recognition to. 

  • To own as genuine or valid; to assent to (a legal instrument) to give it validity; to avow or admit in legal form. 

  • To be grateful of (e.g. a benefit or a favour) 

  • To admit the knowledge of; to recognize as a fact or truth; to declare one's belief in 

  • To report (the receipt of a message to its sender). 

recognize

verb
  • To acknowledge or consider (as being a certain thing or having a certain quality or property). 

  • To match (something or someone which one currently perceives) to a memory of some previous encounter with the same person or thing. 

  • To realize or discover the nature of something; apprehend quality in. 

  • To show formal appreciation of, as with an award, commendation etc. 

  • to cognize again 

  • To have the property to bind to specific antigens. 

  • To acknowledge the existence or legality of; to treat as valid or worthy of consideration. 

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