I think this thread has evolved into a kind of conversation on different topics that are all interesting and amusing. Why not continue?. Just trying to keep it courteous and fair to everybody.

However, if it becomes boring or annoying and someone expresses it (and I feel again this is the case), for the sake of being courteous it should be stopped. Or we could stop it and open a new thread on this subjects, one that would not be related to the bad start this one had.

I agree with you Micron; in the relationship between teacher and student there must be up-->down transmission of knowledge and efforts to avoid misleading information. This is the function of the teacher and also what the student expects to receive.

This knowledge is based on the teacher's concepts of what is right and what is wrong or perfectible in -say- the playing of an instrument.

Whether this accomplishment (i.e. seeing the student improvements) increases the teacher self-esteem or not is not predictable; just everyone knows about his particular feelings. Also this feeling could be considered selfish (in the good sense of the word) -or not.

Sure you will agree with me that not all teachers are always right in what they consider to be the best way of doing something. But for each one, this/her method is right one (his/her own and valid truth)

I believe these are examples of the relativeness of convictions (or "truths")

The issue is very complicated and as I said before, it has been the subject of deep study by the great philosophers.

I'm not one, not even a small one, of course, but I started a course of Introduction to Philosophy when I was a Engineering student. I was surprised by the complexity of this (and many other) subjects that looked trivial at first glance. Being, Truth, Freedom, Reality, Knowledge, Ethics, almost anything important has been - and continues to be- challenged and put in question by philosophers. As a curiosity, I have just checked the Ferrater Mora Phylosophy Dictionary at home. There are 16 pages of it for Truth.

<Added>

Just to clarify that I used "selfish" as the contrary to "altruist"