For whom did President Obama deliver the address?

President Obama has hailed Nelson Mandela as one of the giants of history in an address at the former South African president’s memorial service, comparing Mandela to Mohandas Gandhi, Abraham Lincoln and Martin Luther King. Mr. Obama called him the last great liberator of the 20th century. He urged the crowd of world leaders, celebrities, and tens of thousands of South Africans to embrace his message of peace. But Mr. Obama had a tough message too, questioning whether today’s leaders were living up to Nelson Mandela’s integrity and commitment to justice and peace.

A study in India suggests that speaking more than one language may delay different kinds of dementia , that is, the loss of mental ability. These include Alzheimer’s disease, frontotemporal dementia, vascular dementia, Lewy bodies dementia and mixed dementias. Researchers studied nearly 650 people whose average age was 66. 240 of those studied suffered from Alzheimer’s disease, the most common form of mental decline. 391 of the subjects spoke two or more languages. Investigators found the dementias began about four-and-a-half years later in those who were bilingual compared to those who spoke only one language. The level of education had no effect on the age at the first sign of dementia.