I've always wondered if it isn't too unethical afterall to have enclosed my goldfishy in a tiny tank given her extremely small memory span.
Assuming that it is shorter than the time it takes her to swim from an end to another, she never really "feels trapped", right? - especially if morality of actions affecting others (in the context of the "harm argument") is intricately linked to consciously felt emotional experiences.
Otherwise wouldn't it make sense to then protect things like chairs as well (as long as sentience is what separates moral agents from material things.)
Novice philosophy student here.