Motivation also counts: you will study more effectively if you want to make the world a better place than if you want to be rich, researchers told the British Association science festival in Exeter yesterday.

• 9月9日在英国科学推广协会主办的科技展中，研究人员指出，求学的动机也很重要：想改善世界的学生，学习效率比只想致富的学生好。