What greater weakness can there be than not to know what is the source of one's being, of one's life, of one's senses, of one's knowledge, and what is to be their end? What can be more deeply disheartening than to wonder whether one's soul is, perhaps, a material thing, like a stone or a reptile, corruptible like these base creatures? Is there not more strength and greatness of mind in admitting the idea of a being superior to all other beings, who has made them all and to whom all owe their existence; of a being supremely perfect, who is pure, who had no beginning and can have no ending, of whom our soul is the image and, so to speak, a portion, being a spiritual and immortal thing?