The only way we could say that another world is “inhabited” is due to the presence of beings that would justify us in applying that term to a part of our own world. These beings should possess both intelligence and consciousness on the one hand in addition to having a corporeal form. True, the form can be different from that we possess; but, as with ourselves, the intelligent spirit must be present in and expressed by a living material body. Our inquiry is thus rendered a physical one. This necessitates the presence of beings that have a living body in a world to be termed as inhabited and is not world unsuited for living organisms. Only then, it becomes a “habitable” world.