John XXIII was an advocate for human rights which included the unborn and the elderly. He wrote about human rights in his Pacem in terris. He wrote, "Man has the right to live. He has the right to bodily integrity and to the means necessary for the proper development of life, particularly food, clothing, shelter, medical care, rest, and, finally, the necessary social services. In consequence, he has the right to be looked after in the event of ill health; disability stemming from his work; widowhood; old age; enforced unemployment; or whenever through no fault of his own he is deprived of the means of livelihood."

John XXIII was an advocate for what?