These are the things I proposed to prove concerning the mind, in so far as it is considered without relation to the existence of the body, and from these, and other propositions, it is evident that our mind, in so far as it understands, is an eternal mode of thought, which is determined by another eternal mode of thought, and this again by another, and so on _ad infinitum_, so that all taken together form the eternal and infinite intellect of God. _Conclusion_ The primary and sole foundation of virtue or of the proper conduct of life is to seek our own profit. But in order to determine what reason prescribes as profitable, we had no regard to the eternity of the mind. Therefore, although we were at that time ignorant that the mind is eternal, we considered as of primary importance those things which we have shown are related to strength of mind and generosity; and therefore, even if we were now ignorant of the eternity of the mind, we should consider those commands of reason as of primary importance. The creed of the multitude seems to be different from this; for most persons seem to believe that they are free in so far as it is allowed them to obey their lusts, and that they give up a portion of their rights, in so far as they are bound to live according to the commands of divine law. Piety, therefore, and religion,[42] and absolutely all those things that are related to greatness of soul, they believe to be burdens which they hope to be able to lay aside after death; hoping also to receive some reward for their bondage, that is to say, for _their_ piety and religion. It is not merely this hope, however, but also and chiefly fear of dreadful punishments after death, by which they are induced to live according to the commands of divine law, that is to say, as far as their feebleness and impotent mind will permit; and if this hope and fear were not present to them, but if they, on the contrary, believed that minds perish with the body, and that there is no prolongation of life for miserable creatures exhausted with the burden of their piety, they would return to ways of their own liking. They would prefer to let everything be controlled by their own passions, and to obey fortune rather than themselves. This seems to me as absurd as if a man, because he does not believe that he will be able to feed his body with good food to all eternity, should desire to satiate himself with poisonous and deadly drugs; or as if, because he sees that the mind is not eternal or immortal, he should therefore prefer to be mad and to live without reason--absurdities so great that they scarcely deserve to be repeated.