When a dog runs,” said the naturalist Jakob von Uexküll, “the dog moves his legs; when a sea urchin runs, the legs move the sea urchin.” 10 But even … - Carl Sagan

"Essa é uma das razões pelas quais as religiões organizadas não me inspiram confiança. Que líderes dos principais credos reconhecem que suas crenças talvez sejam incompletas ou errôneas, e criam institutos para revelar possíveis deficiências doutrinárias? Além do teste da vida cotidiana, quem verifica sistematicamente as circunstâncias em que os ensinamentos religiosos tradicionais talvez ja não se apliquem? (É concebível que as doutrinas e a ética que podem ter funcionado muito bem nos tempos patriarcais, patrísticos ou medievais sejam totalmente inválidas no mundo bastante diferente que habitamos hoje.) Que sermões examinam imparcialmente a hipótese de Deus? Que prêmios os céticos religiosos ganham das religiões estabelecidas - ou, nesse aspecto, que recompensas os céticos sociais e econômicos recebem da sociedade em que vivem?
A ciência, observa Ann Druyan, está sempre nos sussurrando ao ouvido: "Lembre-se, você é novo nisso. Pode estar equivocado. Já errou antes". Apesar de todo o discurso da humildade, mostrem-me algo comparável na religião. Acredita-se que as Escrituras sejam de inspiração divina - uma expressão com muitos significados. Mas e se forem simplesmente criadas por seres humanos falíveis?"

Así, en una época en que las religiones tradicionales se han visto sometidas al fuego abrasador de la ciencia, ¿no es natural envolver a los antiguos dioses y demonios en un atuendo científico y llamarlos extraterrestres?

All my life I have wondered about the possibility of life elsewhere. What would it be like? Of what would it be made? All living things on our planet are constructed of organic molecules — complex microscopic architectures in which the carbon atom plays a central role. There was once a time before life, when the Earth was barren and utterly desolate. Our world is now overflowing with life. How did it come about? How, in the absence of life, were carbon-based organic molecules made? How did the first living things arise? How did life evolve to produce beings as elaborate and complex as we, able to explore the mystery of our own origins? And on the countless other planets that may circle other suns, is there life also? Is extraterrestrial life, if it exists, based on the same organic molecules as life on Earth? Do the beings of other worlds look much like life on Earth? Or are they stunningly different — other adaptations to other environments? What else is possible? The nature of life on Earth and the search for life elsewhere are two sides of the same question — the search for who we are. In the great dark between the stars there are clouds of gas and dust and organic matter. Dozens of different kinds of organic molecules have been found there by radio telescopes. The abundance of these molecules suggests that the stuff of life is everywhere. Perhaps the origin and evolution of life is, given enough time, a cosmic inevitability. On some of the billions of planets in the Milky Way Galaxy, life may never arise. On others, it may arise and die out, or never evolve beyond its simplest forms. And on some small fraction of worlds there may develop intelligences and civilizations more advanced than our own. Occasionally someone remarks on what a lucky coincidence it is that the Earth is perfectly suitable for life — moderate temperatures, liquid water, oxygen atmosphere, and so on. But this is, at least in part, a confusion of cause and effect. We earthlings are supremely