The students of Madrid who aspire to enter the University have examined today's philosophy calls selectivity tests. They have had to choose between a text by Nietzsche of the Gaya science and another of the Phaedo of Plato, are how not? In this text speaks Plato of the nature and immortality of the soul and how, when we die, the soul back to the spiritual world, dream world, the world of ideas, the supraceleste world. According to early Christians heaven, what is beyond the physical sky thinking popular; but this supraceleste world isn't physical or spatial for Plato nor for Christian theologians. The simple people conceive it located above, where everything is soft, transparent as air.