Krafft Arnold Ehricke quotes:

Man, the cutting edge of terrestrial life, has no rational alternative but to expand the environmental and resource base beyond earth.

The economic function of space industrialization is to generate jobs on Earth, not in space.

If God wanted man to become a spacefaring species, he would have given man a moon.

One of the most thoughtless statements, parroted ad nauseam ever since rational concern for our environment exploded into an emotional syndrome, calls Man the only animal that soils its own nest. Every animal soils its nest with the products of its metabolism if unable to move away. Space technology gives us for the first time the freedom to leave our nest, at least for certain functions, in order not to soil it.

While civilization is more than a high material living standard it is nevertheless based on material abundance. It does not thrive on abject poverty or in an atmosphere of resignation and hopelessness. Therefore, the end objectives of solar system exploration are social objectives, in the sense that they relate to or are dictated by present and future human needs.

Man's mind and spirit grow with the space in which they are allowed to operate.