你不可能永远快乐,但你可以永远勇敢。
The present state of the system of nature is evidently a resultant of what it was in the preceding moment, and if we conceive of an intelligence which at a given instant comprehends all the relations of the entities of this universe, it could state the respective positions, motions, and general effects of all these entities at any time in the past or future.
The world has the technology - either available or well advanced in the research pipeline - to feed on a sustainable basis a population of 10 billion people.