If we consider merely bodily labour as the cause of wealth, how can we then explain why modern nations are incomparably richer, more populous, more powerful, and prosperous than the nations of ancient times?

• 现代国家在财力、权力、人口以及其他各方面的进展比之古代国家不知要胜过多少倍，如果仅仅把体力劳动作为财富的起因，那么对于这一现象将怎样解释呢?