机械和节省劳力的装置只有在降低制造成本时才具有价值。
We must learn from nature how to use resources efficiently.
If we don't change direction, we'll end up where we're headed.
政府开支的第一条规则:为什么只建一个,当你可以用两倍的价格建两个时?
Growth itself contains the germ of happiness.