Does God Exist?

An argument is a line of reasoning that gives us reasons to accept a conclusion. To examine it, we need to look at its starting point and check every step. An argument can be debated without its supporters being stupid or its opponents dishonest.

Reason is our ability to understand, compare and draw conclusions. We use it to solve a problem, spot a contradiction or look for an explanation. Philosophy applies this kind of thinking to the broadest questions, including the question of our existence.

The word proof does not mean exactly the same thing in every field. In mathematics, a proof establishes a conclusion using precise rules. In science, an explanation must be tested against observations. In an investigation, several pieces of evidence can support one another and lead to a solid conclusion.

Arguments about God also use several methods. Some try to show that a conclusion follows necessarily from their starting points. Others compare possible explanations of the world and our experience. Bringing them together therefore means respecting their differences.

God, if he is the Creator of everything that exists, is beyond the material world. We cannot therefore expect an instrument to measure him as it measures a temperature. This does not remove the need to give reasons for believing in him. It means choosing a method suited to the question.

Our thinking starts from what we know: things exist, change and depend on one another. We also have intelligence, a sense of what is right and wrong, and a search for happiness. The question is what best explains these realities.

The Catholic Church teaches that this search can lead to real certainty about God's existence. A council brings the bishops together with the pope. The First Vatican Council solemnly affirmed this teaching in 1870. This statement concerns the human ability to know God, rather than how easy the path is for each person.^[1]

Saint John Paul II returned to this relationship between faith and reason in Fides et Ratio, in 1998. Faith welcomes what God makes known about himself. Reason seeks to understand, examine objections and recognise reasons to believe.^[2]

The physicist Albert Einstein expressed the need for this dialogue in his own way:

“Science without religion is lame, religion without science is blind.”^[3]

Einstein did not believe in the personal God of religions. A personal God knows, wills and enters into relationships with human beings. This sentence therefore does not justify presenting him as a Christian. It does, however, remind us that scientific research and religious questions do not automatically rule each other out.

Take an ordinary object. It exists because of materials, a process of making it and various conditions. It did not give itself existence. We can then trace what it depends on and ask questions about those other things.

A cause is what produces something or allows it to exist or change. The word therefore does not only mean an event that happened before another. It can also mean something on which another thing depends right now.

A tool held in a hand helps us understand this difference. The tool acts, but its action depends right now on what makes it act. Tracing things back to a first cause means looking for what makes this whole activity possible.

Saint Thomas Aquinas, a Christian thinker, developed five paths of this kind in the Summa Theologiae. They start from change, causes, our fragile existence, degrees of goodness and the order of nature. Their aim is to reach a foundation that does not itself depend on anything else.^[4]

Change and causes

To change is to become different from what one was. Cold water can become hot, but this possibility is not enough to heat it. Something must make this change actually happen. Thomas therefore looks for what enables things to change.

He is not only asking which event might have happened at the very beginning. He is looking for what sustains, right now, things that can act and change. According to his reasoning, a chain of dependencies cannot explain everything if nothing has the power to act in its own right.

The example of tools helps again. Adding tools that pass on an action does not replace what enables them to act. Thomas therefore concludes that there is a first foundation that does not receive its existence and power from anything else.

This conclusion requires us to think about how things really depend on one another. It does not rest simply on our habit of seeing one event follow another. Nor does it depend on discovering a first moment of the universe.

What might not exist

We can then ask a deeper question. The things we find in the world exist, but they might not have existed. Their existence requires conditions that they do not contain entirely within themselves.

Philosophers call this situation contingency. A contingent thing exists, but it does not have to exist, and its existence needs an explanation. The argument from contingency asks why a world made up of such things exists.

Pointing to another dependent thing may explain one step. But why does this whole collection exist? Even an endless series would leave this question open if every member received its existence from elsewhere.

Supporters of the argument conclude that there is a necessary being. This expression means a reality whose existence does not depend on anything else and which could not fail to exist. It would be the foundation of all the things that could fail to exist.

Saying that the universe simply exists, with no further explanation, is one possible answer in the debate. The argument from contingency challenges precisely this answer: why stop the search at a collection of dependent things? It proposes tracing them back to what exists in its own right.

Goodness and the order of the world

The fourth way starts from degrees of goodness, truth and beauty. For example, we judge one action to be more just than another. For Augustine and Thomas, this judgement recognises a standard of justice that goes beyond our preferences. We do not make this standard by choosing what we like.

Thomas then argues that things with limited goodness do not possess, in their own right, all the goodness they show. They receive it from a source that possesses goodness without limit. This source would also be the source of their existence and truth.

The fifth way starts from finality. This word means the regular way something is directed towards a result, as the eye is directed towards sight. Thomas observes that beings without intelligence nevertheless contribute to orderly processes.

He compares this direction to that of an arrow aimed by an archer. This comparison helps explain why a direction can point to an intelligence. According to this way, the order of natural activities also requires an intelligence as its foundation.

The philosopher Edward Feser takes up these questions about change and received existence today. He also examines things made up of parts. An assembled tool depends on its pieces and on their being joined together in order to exist.

According to Feser, explaining this union through other assemblies extends the dependence without providing its foundation. He concludes that there is a cause without parts. This means that it has no elements that need to be brought together for it to exist.^[5]

Another approach considers the beginning of the world. It is called the Kalam cosmological argument. It proposes this reasoning: whatever begins to exist has a cause; the universe began to exist; therefore, it has a cause.

The first point does not mean that everything, without exception, has a cause. It concerns what begins to exist. Before it exists, a thing cannot do anything to produce itself.

The second point needs special examination. The Big Bang is the name of the model describing the expansion of the universe from a very dense, hot initial state. On very large scales, distances in the universe increase on average. This is what we call its expansion.

A mathematical result used in physics also contributes to the debate. It concerns models in which expansion remains positive on average along the paths studied towards the past. In other words, these paths through the universe show expansion rather than contraction on average.

Under this condition, the physical description cannot be extended indefinitely into the past. It reaches a limit that needs an explanation.^[6]

This limit does not, by itself, prove that all physical reality had an absolute beginning. It may call for another physical description beyond the one that reaches its limit. Confusing these two claims would give a scientific result a meaning that goes beyond what it establishes.

We therefore need to distinguish three questions. How has the physical world developed? Did the whole of physical reality have a beginning? Why does it exist, even if its past had no beginning?

The last question remains the question of contingency. It shows why arguments for God do not all rest on a single scientific theory. A change in the model of the beginning would not remove the question of what explains existence itself.

If time and matter themselves began, their cause cannot depend on that same beginning. Supporters of the Kalam therefore seek a cause beyond the limits of time and matter. They ask how a cause acting automatically could produce an effect that begins, without any prior change in that cause. They propose a free choice, capable of bringing the world into existence without being forced to do so by a mechanism.

The word “before” becomes difficult here. Speaking of a cause of time does not necessarily mean imagining a minute before the first minute. It means something that comes first in the explanation: what time depends on in order to exist.

Father Georges Lemaître, a Belgian Catholic priest, proposed the primeval atom hypothesis, which led to the Big Bang theory. His scientific approach does not replace reasoning about God. His life does, however, show that Catholic faith and scientific research can belong within the same mind.^[7]

The existence of a universe is not enough to explain the possibility of life. The way it works must also allow lasting structures and a great variety of combinations. This is where the fine-tuning argument comes in.

Atoms are small units that make up matter. Molecules are combinations of atoms. For stable atoms, stars and chemistry to be possible, certain physical features must meet precise conditions.

A physical constant is a fixed value used to describe how nature works. In the models studied, certain values must stay within narrow, precise limits. Going outside those limits would prevent structures needed for life, such as stable atoms or stars.

These ranges of variation depend on the models used. The expression “fine-tuning” refers to these precise conditions that allow the structures being considered.

A recipe helps us understand the general idea. Having the ingredients does not guarantee the result if their proportions are wrong. In the same way, just any matter, following just any rules, would not necessarily allow a habitable world.

This comparison does not yet establish that someone has actually done any tuning. That is precisely the question to examine. Supporters of the argument consider these conditions more understandable if an intelligence intended to make life possible.

The aim is to compare explanations, without claiming to have a collection of observed universes in which we can count the successes.^[8]

One response proposes the existence of a multiverse. This term means a collection of universes that might have different features. If there were a very large number of possibilities, some universes might have the conditions needed for life.

The philosopher Robin Collins replies that this proposal still requires a mechanism capable of producing these universes. According to him, this mechanism would itself need suitable features. The problem of order would then be shifted rather than removed.^[9]

The debate therefore concerns the best explanation of very particular conditions. The article on the fine-tuning of the universe develops this comparison. The essential idea remains easy to grasp: why does the world have precisely what makes beings capable of observing it possible?

A cell is a small living unit of which organisms are made. The way it works depends on elements that cooperate and on information used with precision. The question of their origin gives rise to another argument for God.

DNA is a long molecule carrying information used by cells. These letters stand for “deoxyribonucleic acid”. Proteins are molecules that carry out many tasks in living things.

The order of the elements in DNA plays a part in making proteins. So it is not enough for elements to be present: their organisation matters too. A message helps us grasp this difference between a quantity of letters and a text that communicates something.

The philosopher of science Stephen Meyer compares the information in living things with organised information whose origin we know. The comparison concerns useful organisation: elements are arranged in an order that allows a specific task. Meyer points out that information of this kind, when we observe its production, comes from intelligences.

He concludes that the information in living things has an intelligent origin. This conclusion is debated: the analogy with a message does not make DNA identical to a human text.^[10]

The researcher Michael Behe develops another approach, called irreducible complexity. By this, he means a system of several parts fitted together and working together. Removing any one of these parts prevents the system from carrying out its basic function.

The basic function is the essential task the system performs. This does not mean that each part would be unable to serve any other purpose.

One example Behe uses is the flagellum of certain bacteria. The flagellum is a molecular structure that helps them move. Movement is the function being studied here. According to him, the cooperation required between its elements presents a difficulty for a wholly gradual construction of the system.^[11]

His critics point, among other things, to other possible uses for some components. Behe and his supporters reply that these uses do not yet explain the origin of the complete working system being studied. This assessment belongs to the argument's supporters; the debate is not unanimously considered settled.

Variations are the differences observed between living things. Their adaptation means what enables them to live in their environment.

Natural selection favours certain variants already present because they allow organisms to live and reproduce more successfully in an environment. It is not a conscious choice. It therefore requires living things on which to act, and its definition alone does not explain the origin of the first life.

Supporters of the argument recognise these phenomena. They challenge the automatic assumption that these phenomena fully explain the organisation of living forms.

We naturally distinguish what we like from what seems right to us. An action can benefit us and still be wrong. We can even recognise an obligation without wanting to fulfil it.

Morality concerns what is right or wrong in our actions. A moral rule is called objective when it does not depend only on the preferences of a person or a society. It remains valid even when someone refuses to admit it.

C. S. Lewis, a Christian writer and thinker, starts from this experience. When we criticise an injustice, we often ask for more than respect for a preference. We expect the other person to recognise a demand that goes beyond both of us.

The moral argument asks what grounds this demand. A description of how matter works does not, by itself, state what we ought to do. Nor is explaining how a behaviour arose enough to establish that it is truly binding.

According to Lewis, a real obligation points to a source of goodness above our choices. God would be this personal source, addressing free beings. Torturing an innocent child would remain wrong even if a society approved of it or nobody discovered it.

He does not claim that someone without religion is unable to do good. His starting point is precisely a widely shared human experience. The question concerns the foundation of goodness, rather than the personal worth of believers or unbelievers.

Saint John Henry Newman develops a similar idea from moral conscience. This expression means our inner judgement about what we ought to do. In it, we can recognise an authority that stands against our own interests, public opinion and even laws.

For Newman, this authority points towards someone greater than us. Following our conscience therefore does not mean declaring everything we want to be right. It means recognising a demand that we have not freely invented.^[12]

Conscious experience means experiencing inwardly what we perceive and think. It is distinct from moral conscience, which concerns right and wrong. Describing what happens in the brain is not yet enough to explain why we experience anything inwardly.

Materialist naturalism is the view that all reality ultimately comes down to material processes. Thomas Nagel, an atheist philosopher, considers that this view fails to account for our conscious experience. Yet he does not believe in God: his criticism highlights a difficulty for materialism without, by itself, proving God's existence.^[13]

The argument from consciousness and reason raises a separate question about our trust in our reasoning. Why can we recognise that a conclusion is true? What connects our thinking to reality?

Alvin Plantinga examines the combination of materialist naturalism with evolution without a guiding intelligence. On this view, our abilities would come from changes and selection favouring survival. Selection preserves what helps living things survive, without directly aiming at true beliefs.

According to Plantinga, beliefs useful for survival might therefore be unreliable on major philosophical questions. He argues that this combination gives us a reason to doubt the reliability of our abilities. If this doubt is justified, it also affects the reasoning used to affirm this combination.

The argument therefore needs to establish this reason for doubt: simply distinguishing survival from truth would not be enough. It does not target all atheist thinking. Its supporters argue that a creative Intelligence better explains our ability to know a world that is itself understandable.^[14]

Happiness raises a different question. We may enjoy a success, an encounter or a discovery, and then still feel that something is missing. Our desire sometimes seems to reach beyond anything a particular experience can give it.

The word infinite means having no limit. Applied to desire, it expresses here a longing for happiness with nothing missing and for love without end. C. S. Lewis puts the reasoning this way:

“If I find in myself a desire which no experience in this world can satisfy, the most probable explanation is that I was made for another world.”^[15]

Hunger points us towards food; thirst, towards water. Lewis suggests also seeing our deep longing as a sign of something real that can fulfil it. This reasoning does not turn every individual wish into a promise of fulfilment.

It concerns a lasting desire that limited goods never seem to satisfy completely. Saint Augustine, a great Christian thinker, expresses this orientation in the Confessions:

“You have made us for Yourself, and our heart is restless until it finds its rest in You.”^[16]

Religious experience

Some people report an inner encounter with God. They describe a presence, peace or love that they experienced as real. These accounts come from different cultures and periods of history.

The philosopher Richard Swinburne starts from our ordinary perceptions. What we perceive initially gives us a reason to believe it, unless there are specific reasons to doubt it. He proposes treating an experience of God in the same way. Testimony then allows others to learn about it.^[17]

This calls for a careful examination of its credibility. The Church does not accept every claim of a supernatural encounter. It distinguishes authentic experience, mistakes and possible explanations linked to how human beings function.

The widespread presence of religious beliefs is also part of the discussion. Plantinga sees it as a sign consistent with a human ability to turn naturally towards God. This sign joins the other arguments; it does not prove a religion by the number of its followers.^[18]

A psychological explanation of this search can be proposed. Yet explaining how a belief arises is not enough to decide whether it is true. Our perceptions also pass through human mechanisms without this automatically making what we perceive unreal.

Can we start from the idea of God?

The ontological argument starts from the idea of God to examine whether his existence follows from it. Saint Anselm of Canterbury, a Christian thinker, defines God as the being than which nothing greater can be conceived. According to him, this being would be greater if it existed in reality than if it existed only in our minds. Limiting it to our minds would therefore contradict its definition.

The philosopher Kant challenges this step. For him, existence is not a quality that makes the description of a being more perfect. Adding that something exists does not change what it would be.

Alvin Plantinga reformulates the argument around possibility and necessity. A possible world means a way reality could be without contradiction. Plantinga reasons about an absolutely perfect being that would exist necessarily, and therefore in every possible reality. If such a being is truly possible, it exists in a possible world. But being necessary there means existing in all possible worlds, including our own.^[19]

The central difficulty concerns this real possibility. Being able to say a description or form a mental image is not enough. The argument remains debated, but it does not simply amount to wishing very strongly that God exists.

Searching despite doubt

Blaise Pascal, a mathematician, physicist and Christian thinker, finally considers our decision to search. His wager is not a proof of God. It addresses someone who does not yet feel convinced.

Pascal compares the stakes. In his reasoning, if God exists, faith opens the way to eternal life. If God does not exist, the costs of this commitment remain limited. Eternity therefore outweighs everything that can be gained or lost during a lifetime.

He therefore considers it reasonable to search, pray and begin practising the faith, even without being certain yet. This approach prepares a person to welcome faith; it does not prove that God exists.^[20]

The arguments above do not remove the difficult questions. Examining them honestly is part of the search itself. Seven objections come up particularly often.

Who created God?

If we ask for an explanation of the world, why exempt God from this requirement? The objection challenges what might look like an exception introduced to save the reasoning.

The answer lies in the initial distinction. The arguments concern what begins or depends on something else. They seek precisely a foundation that does not begin and does not receive its existence. This foundation still needs to be demonstrated; calling it God does not replace that demonstration.

Is God a comforting invention?

Ludwig Feuerbach and Sigmund Freud defended explanations of religion based on human needs. Human beings might attribute to a higher being the power, goodness and protection they desire. This explanation asks why belief is attractive.

But wanting something establishes neither its presence nor its absence. Wanting shade does not stop trees from existing. We therefore need to examine the reasons for belief themselves. A psychological explanation of unbelief would not be enough to refute it either.

Does science make God unnecessary?

Scientific explanations allow us to understand many phenomena without directly bringing in divine action. Why should we add God to a sufficient physical description? The objection deserves more than a general claim that science and faith are opposed.

The answer distinguishes the questions. Describing mechanisms does not yet tell us why these mechanisms and their laws exist. Even a complete physical description would leave open the question of their foundation.

The quantum vacuum is a physical state governed by laws, rather than the absolute absence of all reality. Saying that a universe might come from it therefore does not mean explaining its birth from nothing. The question of why the laws exist remains.^[21]

How can a good God allow evil?

Suffering is the most serious objection. It concerns human violence, but also diseases and disasters. If God loves us and is all-powerful, why does he allow suffering?

Free will is our ability to make real choices about our actions. Saint Augustine links the evil done by human beings to their misuse of this freedom. A creature capable of loving freely can also refuse to love.

Plantinga shows that a logical incompatibility between God and evil is not established simply by considering their supposed presence together. He defends the possibility that freedom involves a real risk of wrong choices. This does not prove that every particular instance of suffering is necessary.^[22]

Swinburne adds that the difficulties of a stable world make courage, mutual help and inner growth possible. This response asks why God might allow certain trials. It does not justify making light of pain or claiming to explain every tragedy. The article on evil and suffering explores this question further.

Do we invoke God only when we do not understand?

The objection targets a poor method: attributing to God what still awaits a scientific explanation. A later discovery would then remove this reason for belief.

The most fundamental arguments ask more. Even if we understood perfectly how something worked, why would it exist? Fine-tuning, for example, questions properties described by science. The world's dependence also remains a question when its mechanisms are known.

Why do religions contradict one another?

If God makes himself known, the diversity of religions may seem surprising. Their claims are not all compatible. We therefore cannot declare them all equally true.

But differing answers do not prove that no truth exists. They may combine an authentic search, partial knowledge and errors. The Church recognises what is true in other religions while maintaining the truth received in Christ.^[23]

The general question of God and the question of true revelation therefore need to be examined in turn. The existence of a Creator does not remove the need to investigate religions. It makes this investigation possible.

Why do sincere people fail to find God?

The philosopher J. L. Schellenberg raises a precise difficulty. A perfectly loving God would want a relationship with every sincerely open person. Why are some unable even to believe in his existence?

This objection concerns honest unbelievers. A believer's lack of consolation is therefore not enough to answer it. It only shows that a real relationship can exist without a felt presence.

The philosopher Paul Moser proposes distinguishing intellectual openness from willingness to undergo a personal transformation. According to him, God seeks a relationship involving the whole person. He might therefore make himself known through a path that goes beyond an immediate answer to a request for proof.^[24]

This response challenges what the objection assumes about how divine love should show itself. It does not allow us to judge the intentions of a particular seeker. A difficulty with faith deserves to be met with understanding and support.

The arguments do not all offer the same kind of conclusion. Classical proofs seek necessity: if their starting points are true, their conclusion must follow. Comparative approaches ask which explanation best accounts for the facts.

Swinburne develops this second approach by bringing together several pieces of evidence. He concludes that God's existence is more probable than his non-existence. This conclusion must not be confused with the certainty that the Church affirms is possible through natural reason. Natural reason means what our intelligence can know by thinking, without starting from a message from God.

Yet the paths come together in a coherent picture. The dependence of things points towards a foundation that exists in its own right. The order of the world and our intelligence point towards a creative intelligence. Goodness and moral conscience lead towards a personal source of goodness.

Personal here means capable of knowing and willing. It does not mean imagining a human being enlarged to the size of the universe. Supporters of these arguments seek an origin that is intelligent, free and capable of a relationship with us.

The researcher Francis Collins illustrates a meeting between scientific work and Christian faith. He converted during his medical training, before his work on the genome. The genome is the complete set of information carried by an organism's DNA.

“The God of the Bible is also the God of the genome. He can be worshipped in the cathedral or in the laboratory.”^[25]

His testimony does not prove God in place of the arguments. It shows how a person can accept their force without giving up scientific research.

A new question then arises: has this Creator made himself known? Revelation means what God communicates about himself to human beings. To examine this question, we also turn to history.

Sources outside Christianity support the historical existence of Jesus. Tacitus mentions his execution under Pontius Pilate. The Gospels also present his claims: he claims to forgive sins in his own name and presents himself as God himself. Examining his divinity therefore means examining the reasons for recognising that Jesus is God.

The resurrection of Jesus means his real return to life after his death. The article studies the empty tomb, the appearances to the apostles and Paul's conversion. It compares the sources for these events and the testimony of the first Christians.

The prophecies announcing Jesus are ancient predictions whose fulfilment in his life is examined. They concern, in particular, his birthplace, his betrayal and the dividing of his clothes.

The question of signs also brings facts into this investigation. A miracle is an extraordinary sign of God's action that goes beyond natural causes. At Lourdes, the Church has recognised healings as miraculous after a medical investigation.

Doctors examine what remains medically unexplained; recognising the miracle is the bishop's responsibility. The miracles of Lourdes are therefore recognised signs, rather than simply accounts of healing.

The Eucharistic miracles discussed here concern the bread consecrated at Mass. This bread becomes the body of Christ. In some cases studied, it has shown features of human tissue. Each case has its own analyses and its own status in the eyes of the Church. The conclusions of one case cannot be extended to the others.

• Thinking about God starts from the real world and our human experience.
• Dependent things lead us to seek a foundation that exists in its own right.
• The beginning of the world and its order raise distinct questions.
• Living things, moral conscience and our intelligence provide further reasons to search.
• The arguments use different methods; their requirements must be respected.
• Objections about evil and God's absence deserve serious answers.
• Recognising a Creator then opens the investigation into Jesus and Revelation.

The conclusion of this investigation is positive: God exists, and human intelligence can know him with certainty. The paths presented lead to a foundation that exists in its own right, a creative intelligence and a source of goodness. They also ground our trust in reason's ability to know what is true.

This certainty does not turn every debated argument into a universally accepted proof. It requires us to examine the starting points and steps without hiding the difficulties. The question of the world's origin therefore concerns us personally. It opens a possibility: being wanted, known and called into a relationship with our Creator.