People are like a collection of stamps, with different shapes, colors, ages and stories they are similar though, since they all are stamps. If we get the chance we may hear their stories or a part of them some day, we may like the whole tales or only a very short part of them and if we're lucky enough to come across nice stories, have good ears and fine memories after some years we may have a collection and it's very possible that this time we call them life-time lessons.
At the third course that I had almost 2 months ago there was one new student who was also going to teach us only for one and half hours of the first session. He used to sit right next to me, listened to the lectures so eagerly and asked questions once he did not understand and he was in his 70s. He studied Medicine when he was young and changed his major to philosophy and is one of the respectful professors of the university and author of some academical books. At the first session he lectured on Neuro-philosophy and then became a student for the rest of the term since there was little discovered in Neuroscience related subjects at the time he was studying Medicine as he said. I was amazed at his humble, modest and enthusiastic spirit and I could not think of any teacher any similar to him through the entire years of my studies.
And in the last two terms, there are two other new students that I see, one is a Ph.D. student of economy and the other is the professor of economy faculty and the tutor of this student. They're trying to define a proposal in economy and in relation with Neuroscience and neural network and for that they need to have some knowledge of nervous system of the body so they attend these classes and both listen and take part in all class activities and also sit for the exams.
I respect these people, no matter how great their places, their titles and their careers are they always remain students.