ergo vs herefore

ergo

adv
  • Consequently, therefore, or thus. 

conj
  • therefore (especially in syllogisms) 

noun
  • An ergonomic factor or characteristic. 

herefore

adv
  • For this reason; on this account; therefore. 

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