"In the end, we are all alone, and that is the ultimate truth of existence."

The context is so important. The context is not just the physical context, but also the historical and cultural context.

The universe would look to a two-dimensional creature who spend its life moving on the service of what turned out to be a globe， it could travel for millions of years and would always return to its starting point， it would never be conscious of what was above it or beneath it.

Every man is his own greatest enemy， and as it were his own murderer.

可持续性不是一种选择；而是我们对后代的责任。