Leo Tolstoy said this quote
“ When a man sees a dying animal, horror comes over him: that which he himself is, his essence, is obviously being annihilated before his eyes--is ceasing to be. But when the dying one is a person, and a beloved person, then, besides a sense of horror at the annihilation of life, there is a feeling of severance and a spiritual wound which, like a physical wound, sometimes kills and sometimes heals, but always hurts and fears any external, irritating touch. ”