Complex sentence: The author asserts that indifference is the worst of attitudes, recalls that he was among the drafters of the Universal Declaration of Human Rights and exhorts young people to look around for topics of indignation.
Split into simpler sentences: The author asserts that indifference is the worst of attitudes. He speaks of his experience among the drafters of the Universal Declaration of Human Rights and exhorts young people to look around for topics of indignation.