Immanuel Kant proposed that life after death is a practical necessity. He said that society cannot function without a code of ethics, and in order for ethics to be meaningful there must be justice. However, justice in this world is not perfect. So if justice is to prevail ultimately, we must survive the grave. And in the world where we find ourselves, there must be a judge who is just, omniscient, and powerful enough to enforce His judgments. If there is no life after death and no God, he said, our ethical decisions are meaningless.
Suppose a person decide to become a burglar. He desire to become a successful burglar. He reason like this: if I want to became a successful burglar I ought to take precaution to make sure that I am not caught in the act of burglaring. Here the burglar is thinking in terms of hypothetical imperative. If he were to think in terms of moral imperative he would be saying to himself: I ought to not be doing this burglary at all.
As soon as we move from the hypothetical to the moral we enter the arena of duty. Duty involves the matter of ethics. Suppose that there is not such a thing as a morally right thing to do. Suppose that right and wrong are merely social conventions. Suppose that all imperatives are all hyphoteticals that never pass into the moral imperatives.
What does this have to do with life after death? Everything. If there is not such a thing as right and wrong, if there is no such a think as moral obligation than there is no such a thing as justness. If there is no such a thing as justness than ultimately there is no such a thing as justice. Justice becomes a mere sentiment. It means the preference of an individual or a group. If the majority in one society prefers the adultery to be rewarded then justice is served when an adulterer received a price for his adultery. But in this schema there is no such a thing as ultimate justice because the will of an individual or a group can never serve as a ultimate norms for justice. It can reveal only a preference.
On the other end if there is such a thing as right and wrong we can talk about real justness. Then justice can be defined in term of rewards and punishment distributed according to what is just.
What Kant and Dostoevsky wrestled with is this: without ultimate justice, can there ever be a sound basis for moral duty? If there is no ultimate justice then why be concern with being just? Pushing this a little further we can say that my moral decision don’t count than I ultimately don’t count. If my actions do not count them my life does not count in the end. Every bone in our body protest against such a negative view of human life.
Kant saw that a life without moral obligation is a life without meaning. Oh to be sure we can assign meaning to our life based on personal preferences and sentiments. But that’s all we have a sentimental wish that our life have meaning. It is a sentimental wish that has both feet firmly planted in midair.
Kant recognized the universal reality of man’s sense of right and wrong. Everyone function with same sense of moral duty.
Kant crucial conclusion was that the moral sense of duty to be meaningful there must be such a thing as justness. For justness right or wrong to me meaningful there must be justice.
Ah, but here is the rub: In this world we recognize that justice is not always done. To many burglars are successful in their burglaring. Does this means that ultimately crime does pay and there is no vindication for the right person?
That is the only conclusion we could reach if in fact there was not ultimate justice. There maybe proximate justice, that is, partial and occasional justice when the burglar is caught and the victims possessions are returned intact, but the scale of justice will be still out of balance. For justness to be meaningful we need more than proximate justice we need ultimate justice.
If ultimate Justice is to be had, than the first requirement that must be met is this: we must survive the grave.
If we do not survive the grave and if justice is not served perfectly in this world than justice is not ultimate and our sense of moral obligation is a meaningless striving after the wind. If ultimate justice is served than we must be there to experience it. Unless we survive the grave we cannot have justice.
We cannot have a trial without a person who is being tried. But neither can be a trial is the only person present is the accused. There must be a Judge. No judge no judgement. No judgement no justice. But this is not ordinary judge that is required, he must be perfectly just…
Dostoevsky’s conclusion: if there is no God, then all things are permissible.
Such a conclusion leaves man and society no real ground for ethics. Without an ethical base society becomes impossible to maintain in the long run.
Therefore on practical ground Kant argue for the existence of God and for life after death two assumptions that are necessary for the very survival of human society, if life is to be meaningful, than there is a God that ensure justice then God must exist.