Discussion on question by flox: Is it possible to live without killing?

Does the continual death of microbes in your gut count as you killing them? What if you scrape scum out from under your fingernails, and some bacteria die of exposure? (The first two points mention animals and plants specifically, but what counts as "life" for the third point?)

@Qami Yes - I have considered killing harmful bacteria as also forbidden. Can we live in a non-bacterial environment?

Is "killing" defined differently for single- and multicellular organisms? Like you can't kill an individual germ but you can harm a person or animal by chopping off a limb. Or is it so absolute that mere constant shedding of skin cells is considered killing?

What is your definition of kill? Things die all the time no matter what you do. How directly does an individual have to be in the death of a thing in order for it to be defined as killing per the alien's definition?