That's nonsense. A baby doesn't know right from wrong, but parents are obliged to care for it. Just because a bear doesn't have responsibility doesn't mean we can shoot it wily-nily, there has to be some justification such as in the example you mention. And commutativity is a property of operations, you probably meant that moral responsibility is a symmetric relation.
Infants have no ability to care for their parents. Do you truly argue that a child, when they become able, has no responsibility to take care of their parents, when they become infirm?
And metaphor need not hew closely to semantics, but having is, linguistically, a ditransitive operation-- technically stative, but the difference isn't important here. I may have responsibility, and I may have responsibility toward you. Responsibility may commutatively have me toward you, if that made sense, or you might commutatively have responsibility toward me, which is the more sensical. In any event, the metaphor is clear.
That infants have no such ability was the whole point of the example. Children do have such responsibilities when they have the ability.
have is actually a transitive word, not ditransitive. An example of the latter is give: A gives B to C. I disagree that there's metaphor here, commutativity is a very technical term and it relates to operations such as addition. So in fact I do think it's relevant that have is stative, because this implies it's not an operation. When speaking of ethical matters it is simply more common to use words like symmetry and reciprocity.
I'm sure I can make the case that bears are the indirect object of my having responsibility -- or rather are not -- but if you prefer, I withdraw the metaphor. The point is that it goes both ways :)
Ah I see now why you would call it ditransitivite. I believe that you would call it an argument/complement to 'responsibility', as 'have' is not an inherently ditransitive verb.
The point about whether it goes both ways is a matter of opinion I think. I feel that humans have an obligation to treat animals well, not necessarily because of how they would feel or their obligations to us, but because it makes humans look bad not to. Kind of like how a gentleman is supposed to be polite regardless of the situation.
That's nonsense. A baby doesn't know right from wrong, but parents are obliged to care for it. Just because a bear doesn't have responsibility doesn't mean we can shoot it wily-nily, there has to be some justification such as in the example you mention. And commutativity is a property of operations, you probably meant that moral responsibility is a symmetric relation.