Kant puts forward a moral argument for the existence of God based on the idea of the Summum Bonum or highest good. He argues that doing one's moral duty is meant to achieve the Summum Bonum of virtue and happiness together. However, evil in the world means this highest good may not be achieved through human efforts alone. Therefore, to give meaning to doing one's duty, the existence of God is postulated as what guarantees that the highest good is ultimately achievable.

2. • Immanuel Kant was a German philosopher.
• He put forward the most famous of all moral arguments
for the existence of God.
• Kant’s moral argument is a part of his ethical theory.
• Kant rejected all attempts to argue from the world to
God, he regarded such an exercise impossible.
• Kant made two essential assumptions:
1.) The universe is fair
2.) The Summum Bonum is achievable
• If these assumptions are shared, then it becomes
necessary to assume that there is a God.
• Kant claims that human beings are rational,
autonomous, moral-decision-makers.
• If human beings are rational, then therefore, they can
make free moral choices.

3. • Kant believed that morality is acting out of duty.
• He suggests that it is reason and not God that is the
basis of morality because we should act in the world as of
there is no God.
• Your moral duty is something you ought to do, not just
because of the consequences but because something is
good in itself.
• The Summum Bonum is the highest good.
• Good moral actions are aimed at this highest good.
• It is the achievement of moral goodness (virtue) and
happiness together.
• Kant believes we can work out our duty through reason,
as it is something which applies universally.
• If it is applicable universally, then it must be what is
right to do.

4. • Moral duty is something you should do because it should
bring about fulfilment as it is the right thing to do.
• The reason to do this is to achieve the Summum Bonum.
• Kant argues that you ought to do your duty if it can be
achieved, so duty can lead to moral goodness and
happiness.
• As a result, doing your duty is either meaningful or it is
not.
• The highest good therefore, must be achievable
otherwise moral goodness is pointless.
• Doing your duty can be meaningful if you cannot
guarantee that the Summum Bonum will be achieved in
this world if you postulate God’s existence.
• God’s existence is the guarantee that ultimately moral
virtue and goodness go together and are achievable.

5. 1.
• Moral action is about doing one’s duty.
2.
• The reason to do one’s duty is to achieve the Summum Bonum.
3.
• However, people can still do their duty, yet still not achieve the
Summum Bonum because of evil in the world.
4.
• Therefore the highest good must be achievable.
5.
• What could make the highest good achievable?
6.
• God.
7.
• Therefore, we should postulate the existence of a God.

6. 1. Every situation is unique – Universal rules aren’t
helpful in the real world where every situation is
different. If no two situations are the same, morality
should be relative not absolute.
2. It is an argument of probability as it is a theory of the
existence of God. We cannot be certain as we will not
know if the Summum Bonum exists until we die.
3. Telling the truth overrides any consequences. There is
no concern for the safety of others because
sometimes it is better to lie in certain situations to
avoid pain and suffering of certain people.