This is a big question. It depends on what you mean by 'human life'.
'Philosophical anthropology' speculates on human beings, among others nature of human condition and practical action. Ethics would be a big chunk.
Perhaps you mean 'life' as Greek 'bios' or physical existence with immanent motion. Then the discussion will be narrowed down to that particular material/physiological aspects.
"Human life" could also mean (it depends on you) human existence and, if so, it will lead to a quest about almost everything in philosophy