these are excellent comments bruno-ken.  I understand what you are saying and empathize with all of it.  In my experience, I have just found, to my regret, that people who are not ready to learn, will just not learn--and the attempt to proselytize to them may in fact do harm.  Here's another quote, more western in its source and from a slightly different angle:

Proverbs
 009:007
He that reproveth a scorner getteth to himself shame: and he  that rebuketh a wicked man getteth himself a blot.

 009:008
Reprove not a scorner, lest he hate thee: rebuke a wise man,  and he will love thee.

 009:009
Give instruction to a wise man, and he will be yet wiser:  teach a just man, and he will increase in learning.

It's not the same point, but it points out that certain people, a wise man, will be very open to discussion, instruction, whatever.  but the fool, the scorner, the wicked man,,,,not sure I would choose those terms,,,,will actually hate you if you try to show him the right direction.  and unfortunately when we begin these campaigns to make things right, we find there are few wise men,,,many more of the others.  so tampering with it, tends to ruin it.  IMHO