If you do not use your arms or your legs for some time, they become weak; when you start using them again, they slowly become strong again. Everyone knows this, and nobody would think of questioning this fact. Yet there are many people who do not seem to know that memory works in the same way. When someone says he has a good memory, he really means that he keeps his memory in practice by often exercising it. If a friend says that his arms and legs are weak, we know that it is his own fault. But if he tells us that he has a poor memory, many of us think that his parents are to blame, and few of us think that it is as much his own fault as if it was his arms or legs that were weak. Have you ever noticed that people who cannot read and write usually have better memories than people who can? This is because those illiterate people have to remember things ; they cannot write them down in a little notebook. They have to remember dates, prices, names, songs and stories; so their memory is being exercised all the time. So if you want a good memory, learn from those people: practise remembering.