Why is the relationship between the destinies of an author and his contemporaries "secret" (ch. 2, p. 7)?

"Is not nothingness one form of perfection (Ch. 3, p. 25)?"

Why does Aschenbach feel "satisfaction or consolation" at the thought that Tadzio won't live long (Ch. 3, p. 28)?

Whose name might have been on Aschenbach's lips as he recalls "early, delicious afflictions of the heart (Ch. 4, p.40)?"

Is the outcome determined entirely by Aschenbach's character and subconscious mind, or do chance and fate play a role?