The Principle of Mediocrity

The spaceship earth metaphor and the principle of mediocrity have both gained wide acceptance among scientifically minded people. But they argue in somewhat opposite directions, with one stressing how typical the earth is while the other stresses how untypical it is. Both oppose arrogance - that we should not expect the world to submit indefinitely to our depredations. The truth is that people are significant in the cosmic scheme of things, and the bisphere is incapable of supporting human life. That's remarkable.