Question: Did Jack Dempsey ever witness Conor McGregor's fights?, Answer:No, Description of Jack Dempsey: American boxer, Fact1: Jack Dempsey died in 1983., Fact2: Conor McGregor's first MMA fight was in 2008.
Step1: In what year did Jack Dempsey die?, Step2: In what year was Conor McGregor's first fight?, Step3: Is #2 before #1?, Wikipedia page for step 1: https://en.wikipedia.org/wiki/Jack_Dempsey, Wikipedia page for step 2: https://en.wikipedia.org/wiki/Conor_McGregor, Wikipedia page for step 3: , not_definitive_answer: False, incorrect_answer: False