The maturity of a civilization is reached when love is extended beyond just loved ones to strangers on the street. Despite exploring the universe, the love for the planet grows deeper, and efforts are made to make it better for the next generation.
The hope is for humanity to reach a point where there is the same love for unknown strangers as there is for loved ones, and this love should be put into the intent of exploring and settling into other planets. Although exploring other planets will happen since humans are explorers, the last days should be spent on Earth.
The speaker talks about their love for the planet and their efforts to understand it better and make it a little better for the next generation. They also emphasize the responsibility we have towards the entire biosphere as the dominant species on Earth.