What does Mandela mean when he says he is “simply the sum of all those African patriots” who had gone before him?

Explanation

Mandela wants to pay his tribute to all the people who had sacrificed their lives for the sake of freedom. he feels that he is the sum of all those African patriots who had gone before him because those heroes of yesterday years had paved the path of co-operation and unity for him. Therefore, he got the support of his people to be able to come to power to bring equality for his own people.