"Gay science" places us on the threshold of Nietzschean thought, since in it Nietzsche is still assembling what will constitute the greatest peculiarity of his work. In the same writing, fragmentary and hesitant, the themes that later will be at the center of his philosophy emerge. He had already crossed the deep valley that has often been unjustly said to be its prophet: nihilism, as closely linked to the positivist belief in science as it is to the metaphysical belief in Christianity. For this reason, in this book both will constitute the target of his struggle against the doubling of the world, against "all metaphysics and physics that suppose an end ... all predominantly aesthetic or religious yearning in a separate world, an afterlife."
