How great was Nelson Mandela?

To some people Nelson Mandela is only the greatest son of Africa.  To others, he is the greatest man of this century. To others, there are many who stand shoulders higher than him. It is interesting what you think?Look at these great men.  Does Nelson Mandela feature among the first three? Abraham Lincoln, JF kennedy, Winston Churchill, William Shakespeare, Leonid Breznev, Mao Tse Tung, Mahatma Gandhi, Kwame Nkruma, Pope John Paul II, Blessed Mother Teresa, Lady Diana?