There is a saying, The happiness of wealth is enjoyable by a person who has tasted the distress of poverty. There is also another common saying, vandhya ki bujhibe prasava-vedana: A woman who has not given birth to a child cannot understand the pain of childbirth. Unless one comes to the platform of actual experience, one cannot realize what is pain and what is happiness in this material world. The laws of nature act accordingly. If one has killed an animal, one must himself be killed by that same animal. This is called mamsa. Mam means me, and sa means he. As I am eating an animal, that animal will have the opportunity to eat me. In every state, therefore, it is ordinarily the custom that if a person commits murder he is hanged.