Well the superiority of the mass in terms of comparative life forms is plain to see.
If this were true, then an elephant would be superior to a human because an elephant is much more massive. It also would mean that killing a 90 kg man would be less bad than killing 2 10 kg toddlers. However, most people would consider a toddler to be more valuable than a man and 2 toddlers even more so.
Is it possible for grass to have purpose and achievements beyond it's base function?
If this is our baseline, since a 5 year old human hasn't achieved anything too important, would it be okay to kill a 5 year old? No. Therefore, some different criteria should be used to measure.
Humans create purpose and achievements, though the question is do those actions have a greater meaning beyond Earthbound humanity itself?
Not all humans do this to a meaningful extent. Someone who has never worked a job hasn't contributed to society, yet if someone shoots them, unless under very rare circumstances, the shooter will and should be charged with homicide.
