"During our brief stay on planet Earth, we owe ourselves and our descendants the opportunity to explore - in part because it's fun to do. But there's a far nobler reason. The day our knowledge of the cosmos ceases to expand, we risk regressing to the childish view that the universe figuratively and literally revolves around us. In that bleak world, arms-bearing, resource-hungry people and nations would be prone to act on their 'low contracted prejudices.' And that would be the last gasp of human enlightenment - until the rise of a visionary new culture that could once again embrace, rather than fear, the cosmic perspective."
Science