Ispectrum Magazine Ispectrum Magazine #05 | Page 29

M.K. : Isn´t a retirement a way to show bravery, too? To me the age of 74 years seems like a good time to retire. Prof. Dr. von Weizsäcker Actually I find it more amusing to travel around the world and try to change peoples’ behavior by teaching them good science and physics. Everybody I met so far was very interested, listening and learning from the things I was saying, which I find important. So, my work is one way of enjoying life. Of course I do enjoy life at home, too. As a matter of fact I have an agreement with my wife: in summer we both have to call off all other exter- nal obligations for four weeks. In this time we stay at a lovely lake resort in Austria and enjoy our togetherness. Christmas is another date, of course, when I enjoy staying with the whole family at our house. M.K. : A little guessing game: How many kWh (Kilowatt Hour) do you need to move a ten kilogram object on the top of Mount Everest? Prof. Dr. von Weizsäcker Yes, very good! I love to ask people this question, because the answer is so astonishing! Every time I ask my students, the answer is everything between 300 kWh and a thousand kWh. Actually the answer is just a quarter – which is absolutely astonishing! In this difference lies one of the hugest problems of our society: our expectation of what a 28 kWh can do is roughly a thousand times less from what a kWh can do in reality. On this assumption, which