what youve said is a very beautiful thing.
to add, in theory:

if there were a man who believed that killing people was a natural part of his life because he has the ability to do it, and he believes that having the ability to do something means that you should demonstrate it, should you not argue with this man in an attempt to prove to him that there is something beyond his ignorant way of thinking? if not simply for him, then perhaps you should argue with this man in order to maybe save the life of his next victim?

i do think that there is something absolutely right in the world, and if i had the willpower i bet i would fight for it as much as possible.

basically what im getting at is that there is existance beyond the life of the individual. to accept that you arent permanent allows you, as an individual, to fight for the immortality of the human race.