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Course 14 · Lesson 2.1

Anselm and the argument of the Proslogion

10 minute read

Lessons in this course

Course 14 outline

Module 1: Arguments, Existence and Necessity

  1. What natural theology attempts and what it does not
  2. Necessary and contingent existence
  3. How to read and test an argument for God
  4. Philosophy of religion today: a map of the field

Module 2: The Ontological Argument

  1. Anselm and the argument of the Proslogion
  2. Gaunilo and the perfect island objection
  3. Kant: existence is not a real predicate
  4. What the ontological argument would show if it worked

Module 3: Cosmological Arguments

  1. Aquinas: the first three ways
  2. Infinite regress: what is the problem?
  3. Leibniz, the principle of sufficient reason and the argument from contingency
  4. Objections: the brute fact reply and the fallacy of composition

Module 4: The Kalam Cosmological Argument

  1. The kalam tradition: Philoponus, al-Ghazali and Bonaventure
  2. The modern argument: whatever begins to exist has a cause
  3. Did the universe begin? Philosophy and cosmology
  4. Objections and replies, and what follows about the cause

Module 5: Teleological and Fine-Tuning Arguments

  1. From Aquinas’s fifth way to Paley’s watch
  2. Hume and the Dialogues Concerning Natural Religion
  3. Darwin and the change in the design argument
  4. The fine-tuning argument: what is claimed and what is debated
  5. The multiverse and other replies

Module 6: The Moral Argument and Divine Hiddenness

  1. The moral argument: Kant, Lewis and contemporary forms
  2. The Euthyphro question and moral realism without God
  3. Evolution and moral knowledge
  4. The argument from divine hiddenness and Christian replies

Module 7: Contemporary Modal Arguments and Evaluation

  1. Possible worlds and modal logic in plain language
  2. Plantinga’s modal ontological argument
  3. Assessing the modal argument: what it needs and what it shows
  4. Weighing the arguments together, and what none of them prove

All courses

Program / Course 14: Arguments for the Existence of God / Lesson 2.1

What you will learn

  • Describe the setting and purpose of Anselm’s Proslogion.
  • State Anselm’s argument in numbered steps.
  • Explain the key phrase that than which nothing greater can be thought.
  • Identify the premise most often challenged.

The big idea

Anselm, a Benedictine monk and later Archbishop of Canterbury, wrote the Proslogion around 1077 to 1078 as a prayer seeking understanding. In its second chapter he argues that God is that than which nothing greater can be thought, that such a being must exist in reality and not only in the mind, since otherwise a greater being could be thought, and so God exists. The argument is short, strange and still disputed. Anselm intended it as faith seeking understanding, not as a way to convince hostile skeptics.

Key terms

Proslogion
The title of Anselm’s short work, meaning roughly an address or discourse. It is written as a prayer.
Ontological argument
An argument that tries to show God exists from the very idea or definition of God, without observing the world. The name comes from Kant.
Existence in the understanding
Anselm’s phrase for being present as an idea in the mind of someone who understands it.
Existence in reality
Existing outside the mind, as an actual thing.
Reductio ad absurdum
A method of argument that assumes a statement is true, shows it leads to a contradiction, and concludes the statement is false.
A priori
Known by reasoning alone, without depending on observation of the world.
Fides quaerens intellectum
A Latin phrase meaning faith seeking understanding, which Anselm used as the original title of the Proslogion.

Background

Anselm (about 1033 to 1109) was born in Aosta, became a monk at the abbey of Bec in Normandy, and later served as Archbishop of Canterbury. He wrote the Proslogion while abbot of Bec. He says in the preface that he had long sought a single argument that would prove God’s existence and nature, and that when he had nearly given up, the argument came to him. He wrote it in the form of a meditation addressed to God.

The central passage is chapter 2. Anselm starts from the belief that God is something than which nothing greater can be thought. He quotes Psalm 14:1, “The fool hath said in his heart, There is no God,” and uses the fool as a figure for someone who denies God. He argues that even the fool understands the phrase, so the thing exists at least in the understanding. Chapter 3 adds that God cannot be thought not to exist.

Anselm’s contemporary Gaunilo, a monk of Marmoutier, wrote a reply on behalf of the fool, and Anselm answered it. The exchange is printed with the Proslogion in most editions and is the subject of the next lesson.

Step-by-step explanation

Step 1: Anselm’s starting definition

Anselm defines God as “that than which nothing greater can be thought.” This is not a claim that God exists. It is a description that believers and unbelievers can both understand. A person who hears the phrase grasps what it means, even if they think nothing answers to it.

Step 2: The argument in numbered form

A common reconstruction runs as follows. 1. God is a being than which nothing greater can be thought. 2. The fool understands this, so God exists in the understanding. 3. A being that exists in reality is greater than one that exists only in the understanding. 4. Suppose God existed only in the understanding. 5. Then a greater being could be thought, one that also exists in reality. 6. But this contradicts the definition in step 1. 7. Therefore God exists in reality as well as in the understanding.

Anselm writes in prose and does not number the steps. Scholars differ on how to reconstruct them, so treat any numbering as an interpretation.

Step 3: The form of the argument

The argument is a reductio. It assumes that the greatest conceivable being does not exist in reality and shows that this leads to an absurdity. The conclusion is not drawn from observing the world, which is why philosophers call it a priori.

Step 4: Chapter 3 and necessary existence

In chapter 3 Anselm adds that it is greater to be unable to be thought not to exist than to be able to be thought not to exist. So God must exist in a way that cannot be denied without contradiction. Many modern philosophers think this second argument is stronger than the first, and Plantinga’s modal version, covered in Module 7, can be seen as a descendant of it.

Step 5: The context of prayer

Anselm begins with a prayer asking God to teach him, and says he does not seek to understand in order to believe but believes in order to understand. This frame matters. The argument is an act of devotion by someone who already believes. Whether it also works as an argument addressed to someone who does not is a separate question, and Anselm’s own answer is not entirely clear.

  1. Can you restate in your own words what that than which nothing greater can be thought means?
  2. Why does Anselm think the fool understands the phrase?
  3. Is it plausible that existing in reality is greater than existing only in thought?
  4. What does it mean to say an argument is a reductio?
  5. Why might a prayer be an odd place to find a philosophical argument?
  6. Does a definition alone seem able to give a conclusion about what exists?

Examples

A painter’s plan

Anselm himself uses a painter. Before painting, the painter has the picture in mind and does not yet have it in reality. Once painted, the picture exists both ways. Anselm uses this to illustrate the difference between existing in the understanding and in reality.

The fool of Psalm 14

In the psalm, the fool says in his heart that there is no God. Anselm reads this as saying that denial of God requires understanding what is denied and still saying that it does not exist. He argues that this is incoherent.

A modern student’s first reaction

Many students feel at first that the argument is a trick, as if a word game could produce a being. The task is to say exactly where the trick lies, or to admit that it is not obviously there. This reaction is common, and philosophers have felt it for nine centuries. (A general observation.)

Different perspectives

Catholic

Anselm is a saint and Doctor of the Church, and the Church honors his method of faith seeking understanding. Thomas Aquinas, the church’s most influential theologian, rejected Anselm’s argument as stated, holding that God’s existence is not self-evident to humans and must be shown from effects. Catholic philosophers therefore divide over the argument.

Orthodox

Anselm lived after the split between East and West, and Orthodox theology has not generally adopted his argument. Many Orthodox writers are uneasy about defining God as the greatest thinkable thing, since they hold that God exceeds all concepts. Others read Anselm sympathetically as a contemplative.

Protestant

Protestant opinion is varied. Karl Barth wrote a famous study of Anselm’s method and read the argument as an exploration of faith, not as a proof for outsiders. Plantinga holds that a modal version succeeds in showing that belief in God is rational, though not that it compels the unbeliever.

Scholarly views

Scholars debate whether Anselm meant a single argument or two (in chapters 2 and 3) and whether he meant it as a proof or as a meditation. There is no consensus, and the question is open.

Skeptical views

Skeptics hold that the argument tries to define God into existence. They say that no definition by itself can show that something exists, and that the argument contains a hidden assumption that existence is a feature that makes a thing greater.

Why it matters

The argument is one of the most discussed in philosophy because it is so short and so hard to fault cleanly. Studying it trains attention to the exact steps of an argument and to the difference between a definition and a discovery. It also shows how deeply prayer and philosophy were joined in the Christian tradition.

Common misunderstandings

Misunderstanding: Anselm gave this as a proof to convert atheists.

Correction: He wrote it as a meditation by a believer seeking understanding. Whether he also thought it would convince a skeptic is debated.

Misunderstanding: The argument says that because God can be imagined, God exists.

Correction: It does not rest on imagination. It rests on a definition and a claim about what is greater. The reasoning is more subtle than that crude summary.

Misunderstanding: Aquinas accepted the argument.

Correction: Aquinas rejected it as a proof for humans, though he thought that God’s existence is self-evident in itself.

Misunderstanding: The argument is obviously fallacious.

Correction: Philosophers have not agreed on where, or whether, it fails. The rejection by Kant is influential, but some philosophers defend modern forms of the argument.

Knowledge check

What is Anselm’s definition of God in the Proslogion?

He defines God as that than which nothing greater can be thought. The phrase is meant as a description that believer and unbeliever both can understand, not as a claim that such a being exists. Anselm uses it as the starting point for his argument that such a being must exist in reality and not only in the mind.

State the structure of Anselm’s argument.

Assume the greatest conceivable being exists only in the mind. Then one could think of a being like it that also exists in reality, which would be greater. That contradicts the definition, since nothing greater was supposed to be conceivable. So the greatest conceivable being must exist in reality. The argument is a reductio ad absurdum.

What does Anselm add in chapter 3?

He argues that it is greater to be unable to be thought not to exist than to be able to be thought not to exist. So the greatest conceivable being must exist in a way that cannot be coherently denied, that is, necessarily. Many modern philosophers see this as the stronger form, and it led to modal versions.

Why is the Proslogion framed as a prayer?

Anselm was a monk and believed in order to understand. He sought to grasp more clearly what he already held by faith. The prayer frame shows that the argument is an act of devotion first. Scholars debate how far it was also meant as an argument for unbelievers.

Think it through

  1. Is it appropriate to mix prayer and argument?
  2. What would you say to a friend who called the argument a word trick?
  3. Does the idea of a greatest conceivable being make sense to you?
  4. Would a successful argument of this kind make worship deeper or only more informed?

Independent assignment

Anselm in your own steps

In your own notebook, write 300 to 450 words. Before you read any summary, read Proslogion chapters 2 to 4 and write Anselm’s argument in numbered steps. Then compare your steps with the reconstruction in this lesson and note any difference. Finish by writing the premise you would question first, and why. Do not send this to anyone.

Further study