The critical response to Mortality was largely positive with friends and admirers of Hitchens praising both his character in confronting his death and the way that this was transferred onto the page. In a glowing review of Mortality in The New York Times , Christopher Buckley described Hitchens' seven essays as "diamond-hard and brilliant" and "word-perfect." He wrote that it was "sobering and grief-inducing to read this brave and harrowing account of his "year of living dyingly" in the grip of the alien that succeeded where none of his debate opponents had in bringing him down." Buckley was a friend of Hitchens.  Colm Tóibín fondly wrote in The Guardian of his experiences with Hitchens, opining that "he was the best company in the world" and offered praise for Mortality , writing that "in this book he does everything to make sure that his voice remains civilised, searching and ready to vanquish all his enemies, most notably in this case the dullness of death and its silence."  In The Observer Alexander Linklater was also complimentary. Referring to John Gray's description of Hitchens as "one of the greatest living writers of English prose",  Linklater responded that "the only word of that which is certainly untrue is that Hitchens is now no longer living." He also noted: "The real struggle in Mortality is not with mortality. Hitchens cleaves to the logical conclusion of his materialism. He hints, rather, at a fear of losing himself, of becoming an imbecile, someone who might, in terror and pain, say something foolish or (God forbid) religious near the end, to give his enemies satisfaction. The true struggle of his last writings is to remain himself, deep in the country of the ill, for as long as he can."  Another positive review came from the magazine where Hitchens started his career, The New Statesman . George Eaton wrote that Hitchens' final work had "a timeless, aphoristic quality". 
While Christopher Hitchens devoted most of his criticisms towards political figures that he disagreed with, these criticisms extended to and involved a myriad of different famous people, from celebrities to other authors and philosophers. When looking at his many criticisms and scathing attacks of others, some of the most famous include that of Mel Gibson, Princess Diana, President Bill Clinton, Reverend Jerry Falwell, Bob Hope and Mother Teresa , as mentioned earlier. Out of the lot of these, his criticisms of Mother Teresa and Princess Diana were likely the most controversial, due primarily to the fact that they happened at a time when both of these figures were idolized by nearly everyone. In fact, his quotes on Princess Diana came very shortly after her untimely death, while the whole of Britain, and most of the world, were still in shock. However, that was largely the point of his criticisms in the first place. He believed that their sorrow was misplaced, calling it "contrived hysteria". This was due, in part, to his thinking of Princess Diana as a "silly, trivial woman".