Giovanni Loi sat at the front of the hall for the lecture by the learned professor. The subject was age, something Giovanni knows a lot about. He is 98, looks about 70 and is a fit as a fiddle. He walked up the steep hill to the lecture and was going to walk home afterwards. After all, he is almost a youngster when compared with others in his community in the hills of Sardinia. The oldest person recorded here was 113, but in the last 20 years there have been over 3000 centenarians, out of just 1.6 million people.