God and theodicy

17th November 2020

For centuries, since Aristotle, this issue has been among the most important points. The essence of metaphysics, essential to Descartes in particular for this reason, but also for epistemological reasons. We need God to be sure that our understanding of nature and the world is accurate.

Two main parts

  • God
  • The main theological problem: evil
We'll be referring to God as he/him not because God is supposed to be male, but because along history he's been called with masculine pronouns.

Main questions

  • What are God’s attributes?
  • Does God exist?
  • How many Gods do exist?
  • Is it possible to demonstrate God’s existence?
  • How?


Types of demonstration

We may demonstrate God’s existence in two ways:

  • a priori: a demonstration independent from existence; a demonstration that starts from the cause and from it all the effects are derived.
  • a posteriori: a demonstration which starts from the effects and go back to the cause;
    an example may be [[ God and Theodicy#D’Aquino’s Cosmological Argument|the Cosmological Argument ]]

Demonstration can be made in two ways: One is through the cause, and is called “a priori”, and this is to argue from what is prior absolutely. The other is through the effect, and is called a demonstration “a posteriori” […] When an effect is better known to us than its cause, from the effect we proceed to the knowledge of the cause. And from every effect the existence of its proper cause can be demonstrated, so long as its effects are better known to us; because since every effect depends upon its cause, if the effect exists, the cause must pre-exist. Hence the existence of God, in so far as it is not self-evident to us, can be demonstrated from those of His effects which are known to us.

Tommaso D'Aquino, Summa Theologica

The existence of God is not self-evident, it doesn’t appear as clear and obvious; it isn’t trivial and has to be demonstrated.

There are five ways of demonstrating God’s existence, examined in D’Aquino’s Summa Theologiae:

  1. The argument from motion
  2. The argument for efficient causes
  3. The argument from contingency
  4. The argument from gradation of being
  5. The argument from design

D’Aquino took Aristotle’s proof of God’s existence as a model for his demonstration.

D’Aquino’s Cosmological Argument

Note: a cosmological demonstration isn’t necessarily an a posteriori demonstration.

The argument from efficient causes

The second way is from the nature of the efficient cause. In the world of sense we find there is an order of efficient causes. There is no case known (neither is it, indeed, possible) in which a thing is found to be the efficient cause of itself; for so it would be prior to itself, which is impossible. Now in efficient causes it is not possible to go on to infinity, because in all efficient causes following in order, the first is the cause of the intermediate cause, and the intermediate is the cause of the ultimate cause, whether the intermediate cause be several, or only one. Now to take away the cause is to take away the effect. Therefore, if there be no first cause among efficient causes, there will be no ultimate, nor any intermediate cause. But if in efficient causes it is possible to go on to infinity, there will be no first efficient cause, neither will there be an ultimate effect, nor any intermediate efficient causes; all of which is plainly false. Therefore it is necessary to admit a first efficient cause, to which everyone gives the name of God.

Everything has a cause and nothing can be the cause of itself. Descartes doesn’t share this view, since to him God is the cause of himself.


  1. everything is necessarily caused by something else
  2. nothing can be caused by itself
  3. to take away the cause is to take away the effect
  4. Thus, it must exist a first cause: such cause is God

If we don’t find a first efficient cause, we won’t stop going back.


  • Even admitting this demonstration works, it doesn’t necessarily follow that God has the properties D’Aquino uses. We need something more to prove the properties.
  • It’s not impossible to have an infinite regress, which D’Aquino denies; we can imagine a never ending sequence, as the sequence of numbers

The argument from design

The fifth way is taken from the governance of the world. We see that things which lack intelligence, such as natural bodies, act for an end, and this is evident from their acting always, or nearly always, in the same way, so as to obtain the best result. Hence it is plain that not fortuitously, but designedly, do they achieve their end. Now whatever lacks intelligence cannot move towards an end, unless it be directed by some being endowed with knowledge and intelligence; as the arrow is shot to its mark by the archer. Therefore an intelligent being exists by whom all natural things are directed to their end; and this being we call God.

It’s not a chance that such a complex connection among beings results from chance. Some entity, God, has organized and structured everything from the origin.

Nature is like a watch which has all tiny complex elements that work in harmony, and there has to be a watch maker.

Charles Darwin explained we can demonstrate existence through chance and necessity, which are at the center of his theory of evolution.

Also seen in David Hume’s Section XI

Anselm’s Ontological Argument

The Ontological Argument is defined so because it starts from being. It has been defined by Kant for the first time.

Among the a priori demonstrations, there’s Spinoza’s one, too; it starts from substance.

[[ Anselm’s Ontological Argument.pdf|The Ontological Argument ]] by Anselm of Canterbury.


  1. God is something than which nothing greater can be thought;
  2. God exists in the mind since even the fool1 (the atheist) can think of something than which nothing greater can be thought;
  3. God can’t just be in the mind, since it’s greater to be in reality than it is to be only in the mind;
  4. since being in reality means being more than just being thought, and since nothing greater can be thought, God has to be in reality, thus he must exist.

If God didn’t exist, we would have a contradiction since we would say there is an entity that is greater than him, which exists in reality and not only in the imagination; therefore, since to be in reality is more than to be in the mind only, it would exist an entity which is more than God, and this contradicts the very definition of God.

Ganulio’s objection

The objection by the monk Ganulio of Marmoutiers

They say that there is in the ocean somewhere an island which, because of the difficulty (or rather the impossibility) of finding that which does not exist, some have called the “Lost Island.” And the story goes that it is blessed with all manner of priceless riches and delights in abundance, much more even than the Happy Isles, and having no owner or inhabitant, it is superior everywhere in abundance of riches to all those islands that men inhabit. Now, if anyone tell me that it is like this, I shall easily understand what is said, since nothing is difficult about it.
But if he should then go on to say, as though it were a logical consequence of this: You cannot any more doubt that this island that is more excellent than all other lands exists somewhere in reality than you can doubt that it is in your mind; and since it is more excellent to exist not only in the mind alone but also in reality, therefore that it must needs be that it exists. For if it did not exist, any other land existing in reality would be more excellent than it, and so this island, already thought by you to be more excellent than others, will not be more excellent. If, I say, someone wishes thus to persuade me that this island really exists beyond all doubt, I should either think that he was joking, or I should find it hard to decide which of us I ought to judge the bigger fool.

Ganulio applies Anselm’s line of reasoning to a perfect island. Such island, following Anselm’s argument, must be real to be perfect; hence, if it’s not, the other islands in the world should be more perfect than the perfect island I imagine in my mind.

Furthermore, in another passage Ganulio presents another counterargument: many among the ones who believe in God state that he can’t be fully known and his definition goes partly beyond human understanding. If it is so, the Ontological Argument wouldn’t work.

D’Aquino’s criticisms

Perhaps not everyone who hears this word “God” understands it to signify something than which nothing greater can be thought, seeing that some have believed God to be a body. Yet, granted that everyone understands that by this word “God” is signified something than which nothing greater can be thought, nevertheless, it does not therefore follow that he understands that what the word signifies exists actually, but only that it exists mentally. Nor can it be argued that it actually exists, unless it be admitted that there actually exists something than which nothing greater can be thought; and this precisely is not admitted by those who hold that God does not exist.

Tommaso D'Aquino, Summa Theologica, I, q. 2, ad secundum

  1. Doubting the evidence of the definition of God
  2. Granting the above is true, it doesn’t follow necessarily that I accept the passage from mind to reality.

We can’t move from the domain of thought to the domain of reality, it’s not an automatic passage.

The answer regarding the existence of God includes in itself the question, which is to prove this. A requirement to prove the existence of God is admitting his existence, which is nonsense.
Petition principi: begging the question

Kant’s criticisms

A hundred real thalers do not contain the least coin more than a hundred possible thalers. For as the latter signify the concept and the former the object and positing of the object, should the former contain more than the latter, my concept would not, in this case, express the whole object, and would not therefore be an adequate concept of it. My financial position is, however, affected very differently by a hundred real thalers than it is by the mere concept of them (that is, of their possibility.)

Immanuel Kant, Critique of Pure Reason, Trascendental dialectics, A599/B627.

Kant’s conclusion is that existence is not a property, but it’s a position.

Taken the definition of a certain amount of money, in the mind there’s no difference of properties between it and the actual objects which make it the same amount.

You don’t have more properties if you exist, you're only in another domain of the mind. Anselm instead believes that being in reality means being more, being greater.
Existence doesn’t add anything to an entity.

Descartes’ proofs

18th November 2020

René Descartes’s Third Meditation

Reactions of the catholic church

7th December 2020

Averroes: philosophy and religion must be separated.
Considered dangerous by christian church: if it would be so, the Christian church would’ve been no domain on the human dimension, not in the religious only. Consider the historical context.


Next topic: Section XI

  1. The fool hath said in his heart, “There is no God” ~Psalm 14, 1 



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