Once a philosopher was traveling down a river in a small boat

Once a philosopher was traveling down a river in a small boat. While he was crossing the river he asked the boatman: ” Have you ever heard about Philosophy? ” “No” , I haven*t " said the boatman. “I*ve never heard about it. What is it? ” “I am sorry for you, indeed,” replied the learned man, “you have lost a quarter of your life as it’s a very interesting science! ” Several minutes later the philosopher asked the boatman another question: “Did you hear about Astronomy, when you were at school? ” “No, I left school many years ago and I forgot all about it.,” was the answer. To this the philosopher answered that he was really sorry for the man, and he thought that the boatman lost a second quarter of his life. Some minutes passed and the passenger again wondered if the man had ever heard about Algebra. And the man had to admit that he had never known anything about it. “In that case you certainly lost a third quarter of your life! ” said the scientist. At that very moment the boat struck on a big stone. The boatman jumped and cried: “Have you ever learnt swimming (to swim)? ” “No,” was the answer. The boatman explained sadly to the philosopher that he was sure the scientist had lost his whole life as the boat was sinking