The Summum Bonum in 7 easy steps
1. Meaning of the words: Literally translates as supreme good. Kant uses it to mean the highest happiness.
2. What it is: Received in the afterlife, the summum bonum is a reward for acting out of one’s duty, as long as
one acted autonomously. The summum bonum is a happy, fulfilled state of mind.
3. Why it’s part of Kant’s theory: The summum bonum is a necessary reward as otherwise it would not be
rational to act morally e.g. Hitler did terrible things but killed himself before receiving punishment, while morally
good actions often go unrewarded and unnoticed e.g. heroes dying in war. The existence of the reward
therefore makes being morally good a rational decision- it ensures justice is served for those who acted
morally/dutifully
4. How to get the summum bonum: The categorical imperative has to have been followed in order to have
known what your duty was/is and then acted on. The reward is not available to those who performed ‘good’
actions for any other reason (e.g. because of the consequences or because they acted purely out of emotion)
5. Why you must accept the 3 postulates: If you accept the truth of the summum bonum you must also accept
the truth of the following:
 There is a God: only a divine being could have the knowledge required to reward the dutiful (God is
omniscient= all knowing). Furthermore, this reward of pure joy could only be given by a wholly good being (God
is omnibenevolent= wholly good and loving). Lastly, this kind of reward could only be given by a being with the
power to do so (God is omnipotent= all powerful). Kant argues the innate moral law also acts as proof of
God’s existence- claiming it is the best and only rational reason to accept the truth of God’s existence
 We have Immortality: There must be an immortal soul because the reward of highest happiness could not
possibly be obtained in a mortal life as such a joy could not be experienced in this, physical, world.
Furthermore, a reward would only really make sense when we have finished making moral decisions (i.e. when
we die). The summum bonum is therefore awarded to the immortal soul in the afterlife and, for that reason,
many have compared the summum bonum to heaven.
 There is the possibility of Freedom: To obtain the summum bonum you must have acted freely, or a reward
would not be appropriate. Therefore, freedom must be possible. Because someone who acts morally, but not
freely, cannot obtain the summum bonum this is one reason why you should not lie or undermine the autonomy
of others. It is another good reason not to use others as a means to an end.
Together these are known as the Postulates of Practical Reason. What Kant means is that they explain why
being moral is also being rational. Morality is reason made practical (i.e. put into practise).
6. The question of whether the summum bonum is actually a goal: Some people argue that the summum
bonum is actually a goal that makes Kant’s approach to ethics teleological (telos meaning ‘goal’ or ‘end’) rather
than deontological (deon meaning duty). However, we can respond that if you acted morally only to obtain the
summum bonum you wouldn’t have acted dutifully and so you wouldn’t actually get the reward at all. Therefore
it would be irrational to work towards a goal if working towards that goal actually deprived you of the goal
therefore treating the summum bonum as a goal is irrational.
7. Criticisms: ???