The essential feature of the morality built upon the basis of Hartmann's philosophy is the realization that all is one and that, while every attempt to gain happiness is illusory, yet before deliverance is possible, all forms of the illusion must appear and be tried to the utmost. Even he who recognizes the vanity of life best serves the highest aims by giving himself up to the illusion, and living as eagerly as if he thought life good. It is only through the constant attempt to gain happiness that people can learn the desirability of nothingness; and when this knowledge has become universal, or at least general, deliverance will come and the world will cease. No better proof of the rational nature of the universe is needed than that afforded by the different ways in which men have hoped to find happiness and so have been led unconsciously to work for the final goal. The first of these is the hope of good in the present, the confidence in the pleasures of this world, such as was felt by the Greeks. This is followed by the Christian transference of happiness to another and better life, to which in turn succeeds the illusion that looks for happiness in progress, and dreams of a future made worth while by the achievements of science. All alike are empty promises, and known as such in the final stage, which sees all human desires as equally vain and the only good in the peace of Nirvana.