[Why do the very aged become so old?].

Some men can obtain hundred years or more, but the grounds are as yet unknown. Till now medical research has given no specific clues. Intensive consideration shows that life under quite natural (no longer found), not too hard social and climatic conditions (more maritime than arid) and in mountainous regions is decisive. It is clear that few territories of the earth come into consideration. The specific mental situation of mountain dwellers which contrasts in important points to that of the inhabitants of flat country, plays a decisive part.