Two school friends, Wise Friend (Wi-Fri) and Intelligent Friend (I-Fri) are having a chat. Wi-Fri: How do you learn a subject at school? I-Fri: We relate words with a happening or an event in order to understand it. Wi-Fri: Like? I-Fri: Sugar tastes sweet, chilly tastes pungent, the Sun rises and sets. Later we do this with more complicated terms like gravity and so on. Wi-Fri: Does everybody “understand” it? Not remember the words, like the computer does, I mean “really” understand? I-Fri: Hmm... I don’t think so. Wi-Fri: What makes you say that?