It comes directly from the math of double entry bookkeeping.
In my analogy, individual people do need to take care to ensure they don't run out of water. But you don't need to worry that if it rains a lot this year, there won't be any rain left for your children.
In my analogy, individual people do need to take care to ensure they don't run out of water. But you don't need to worry that if it rains a lot this year, there won't be any rain left for your children.