Philosophical proofs

regarding the existence of God

Introduction

In the quest to understand the existence of God, philosophers and theologians have developed a variety of arguments over the centuries.
👉 These arguments are divided into two main categories:

  • A posteriori arguments: based on experience and observation of the world.
  • A priori arguments: based on pure reason, independent of any experience.

Here, we will explore these different approaches, drawing on key figures such as Thomas Aquinas, Anselm of Canterbury, and William Lane Craig.

???? The Cosmological Arguments

???? The Kalam and the First Cause

The Kalam argument, popularized by William Lane Craig, is based on three steps:

  1. Everything that begins to exist has a cause.
  2. The universe had a beginning.
  3. Therefore, the universe has a cause.

 Why does this hold?

  • The first premise is intuitive: every effect has a cause.
  • The second is supported by modern science, such as the Big Bang theory.
  • The conclusion points to a cause outside of time and space: an eternal and transcendent God.

???? The Five Ways of Thomas Aquinas

In his Summa Theologiae, Thomas Aquinas proposes five ways to prove the existence of God.
One of the best known is the argument from motion:

« Everything that is in motion was put in motion by something else. »


???? For example:
A ball doesn’t roll by itself — someone or something must have pushed it.

Metaphorical version

Imagine the universe as a balloon inflating. If the balloon started to inflate, someone must have blown into it. This “someone” cannot be inside the balloon (because before the balloon, there was nothing) → they must be outside (like God).


 Conclusion: There must be an Unmoved First Mover (one that was not set in motion) who moves everything else, whom we call God.


Modern objection: the law of inertia.
But the argument is metaphysical, not scientific. It seeks a first cause, not a mechanical explanation.

???? Teleological Arguments – Intelligent Design

???? Is the universe too finely tuned to be a coincidence?

  1. Every design implies a designer.
  2. The universe and life show clear signs of design.
  3. Therefore, the universe and life have a designer..









Examples of “fine-tuning”:





    

  • The position of the Earth
    • 




  • The composition of the atmosphere
    • 




  • The complexity of DNA
    • 




  • The architecture of the human eye
    • 











Objection: Natural evolution explains complexity.
Response: Evolution does not explain the origin of the universe nor the emergence of life. The apparent design suggests an intelligent Creator.














⚖️ The Moral Argument





???? Is there a universal moral law?














    

  1. Every law requires a lawgiver.
    2. 




  2. There exists an objective moral law.
    3. 




  3. Therefore, there exists a moral lawgiver.
    4. 






 Why is this relevant?





    

  • Some actions (murder, torture…) are universally recognized as wrong.
    • 




  • If morality depended solely on cultures, nothing would be objectively wrong.
    • 






Objection: Morality could be the product of society or evolution.





But this does not explain why certain things are morally condemned at all times and in all places.
👉 This therefore points to a transcendent Being who is the source of goodness: God.














???? The Ontological Argument





???? A purely logical reasoning









Formulated by Anselm of Canterbury:





    

  1. God is the being than which nothing greater can be conceived.
    2. 




  2. It is greater to exist in reality than only in the mind.
    3. 




  3. Therefore, God must exist in reality.
    4. 











Idea: If God existed only in our mind, then we could conceive of an even greater God: one who truly exists. That would be contradictory to the very definition of God.










Critique: A mix between concept and real existence.
But the argument continues to be debated among philosophers of religion.














✨ Conclusion









The arguments for the existence of God are numerous and varied:










    

  • Cosmological: why does the universe exist?
    • 




  • Teleological: why is it so finely tuned?
    • 




  • Moral: why do universal moral standards exist?
    • 




  • Ontological: what does it mean to conceive a perfect being?
    • 







These questions have spanned centuries and remain at the heart of philosophical and theological debate.





???? If these topics interest you, don’t hesitate to explore them more deeply, because believing in God is not only a matter of faith but also of reason. For historical evidence, check out this article.