1. Leibniz

2. Background
Gottfried Wilhelm Leibniz was born in Leipzig, Germany, on July 1, 1646
Leibniz was the son of a professor of moral philosophy
He was a personal aid to many noblemen.
Worked as legal advisor as well as official historian

3. Importance Leibniz made many significant advances in symbolic logic.
Leibniz also tried to correct the errors of Cartesian metaphysics without throwing away its main structure.

4. Philosophy
Leibniz’s philosophy, found in his Monadology and Essays in Theodicy, are summarized into three main principles….

5. Philosophy 1. The Principle of Identity
2. The Principle of Sufficient Reason
3. The Principle of Internal Harmony

6. Principle of Identity
Leibniz divided all propositions into 2 kinds, Analytic and Synthetic.
Analytic
Synthetic
1. True by definition
1. Not true by definition
2. Necessary
2. Not Necessary
3. A Priori
3. A Posteriori

7. Identity
Analytic Propositions were the positive counterpart of the principle of noncontradiction.
This states that the negation of every analytic sentence is a self-contradiction.
Analytic:
1. All Bachelors are men
2. 2+3= 5

8. Examples Synthetic Propositions: 1. The cat is on the mat
2. In 1492 Columbus sailed the ocean blue

9. Identity
Leibniz claimed that all Synthetic sentences were Actually Analytic.
Synthetic sentences were relative to time. (i.e. Fluffy the cat was on the sofa at time X.)
From God’s point of view, all true sentences are necessarily true, even if it doesn’t seem to be for humans.

10. Identity
The characteristic of Fluffy being on the sofa at time X is as much of a characteristic as Fluffy being a cat.
This shows how Leibniz believed in a predestined world from God’s point of view.

11. Principle of Sufficient Reason
Leibniz believed that for anything to exist, there must be a reason why it exists and why it exists as it does. These reasons should also be open to human inquiry.
He claimed that this Principle was the Main Principle of Reality. Whoever rejected it was Irrational.

12. Example
If Fluffy the cat is on the sofa, then there must be a reason that it exists at all.
There must also be a reason why it exists on the sofa instead of on the roof.

13. Sufficient Reason
Leibniz applied this way of thinking to the universe.
Leibniz wondered why something existed rather than nothing.
Leibniz concluded that there must be an uncaused cause, an all-perfect God who’s being was necessary.

14. Sufficient Reason
According to Leibniz’s philosophy, one can prove the existence of God from rationality and the proposition that something exists instead of nothing.

15. Principle of Internal Harmony
Leibniz believed that If there is a God, He must be both rational and good.
God must also desire and be capable of creating the maximum existence possible:
(Metaphysical Perfection) &
maximum activity possible :
( Moral Perfection)

16. Internal Harmony
According to this, at creation, God created only the possibilities that would guarantee the maximum moral and metaphysical perfection.
Leibniz also based his claim that this is the best of all possible worlds off of this.

17. Example Fluffy the cat MUST be on the sofa at 4:20.
If Fluffy the cat is not on the sofa at 4:20, then it is not Fluffy the cat.

18. Monads
Many philosophers following Descartes viewed reality as being made up of substances.
According to Leibniz, these were Monads.
Monads: units of psychic force.
He believed that these were the simplest and realest “things” that existed.

19. Monads Monads were not a material substance.
Everything was a product of a monad or group of monads.
He also believed that each monad is a mirror of the entire universe.
He believed that these monads (or groups of monads) were conscious.
Lastly, Leibniz believed that the clusters of monads that were free, were human beings.