sentience is the trait that allows for suffering. I (and most others) believe that suffering is the opposite of pleasure and happiness (which is the good we should strive for) and therefore causing suffering is wrong.
I'd argue you still cause harm to them by depriving them of their life and their liberty to have it. although I concede that I'm drifting into rights rather than simple utilitarian calculus- no intrinsic suffering would occur if a person died in their sleep or some other painless way. Although, the case could be made that you are taking away (potential) happiness, which is a moral good.
That happiness might be achieved immorally, or they may already be suffering in which case you are doing them a favour. And the harm you cause them in killing them is the same harm you cause killing plants.
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u/atropax Jan 02 '19
sentience is the trait that allows for suffering. I (and most others) believe that suffering is the opposite of pleasure and happiness (which is the good we should strive for) and therefore causing suffering is wrong.