So if a 78 years old is doing his/her job perfectly you should replace him/her with a much much younger person? And why is that? Having a job is not something distributed it is something you are entitled if you are up to it! Yes of course having an older but capable person doing a task will stop a less talented capable person to get the job. If that less talented person happens to be young do I have to stand up and give my seat? I am not that type of old geezer who gives up without a fight. Let me tell you why a 75 year old might also want to work 6 hours a day and also study; for the same reason your president at this advanced age is interested in Nanotechnology which I am not sure you ever heard of!!
Saudis warns U.S. that 9/11 responsibility law would erode investor confidence in America (Reuters)
from the article: Peres: Israel shouldn't force workers to retire at official pension age