The fact that he is not willing to kill his grandmother to save the chickens doesn’t imply that chickens have 0 value or that his grandmother has infinite value.
Consider the problem from an egocentric point of view: to be responsible for one’s grandmother’s death feels awful, but also dedicating your life to a very unlikely possibility to save someone who has been declared dead, seems awful.
The fact that he is not willing to kill his grandmother to save the chickens doesn’t imply that chickens have 0 value or that his grandmother has infinite value.
Consider the problem from an egocentric point of view: to be responsible for one’s grandmother’s death feels awful, but also dedicating your life to a very unlikely possibility to save someone who has been declared dead, seems awful.