The Necessity of God

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The Necessity of Gods Existence

• Daniel von Wachterhttp//daniel.von-wachter.de

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The traditional claimGod exists necessarily
(GN)

• The intuition Gods non-existence is not a
  possible alternative.
• The question How should God exists be
  interpreted, and is it true?
• I shall not discuss ontological arguments.
• I shall not give arguments for theism.
• If there is a God, does he exist necessarily?

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Historical examples Anselm

• Anselm of Canterbury (1033-1109) You exist so
  truly, my Lord God, that you cannot even be
  thought of as not existing... Whatever exists
  except you alone can be thought of as not
  existing. You alone ... enjoy existence to the
  fullest degree of all things ... everything else
  enjoys being in a lesser degree. (Proslogion, ch.
  3)

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Historical examples

• John Duns Scotus You Lord are uncaused,
  ingenerable and imperishable you cannot possibly
  not exist, because you are neces-sary being from
  yourself (ex te necesse esse) (Tractatus 91)
• Thomas Aquinas God is identical with his essence
  and his being.
• Leibniz Whilst created world exists contingently
  and depends on God, God exists necessarily and
  depends on nothing. He exists of absolute and
  metaphysical necessity and is the last cause of
  everything. (De origine...)

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Today

• Contemporary philosophers usually reject the view
  that God exists necessarily.
• They use the concept of necessity from logical
  empiricism, namely logical necessity.
• I shall explain the LE doctrine, criticise it,
  propose a different concept of necessity, and
  argue that God exists necessarily in this sense.

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Logical empiricism

• LE was exported by AJ Ayer and was soon
  dominating. The rival view was not exported and
  never prominent.
• LE reacted against phenomenology (Husserl,
  Scheler) and rejected necessity claims about the
  world (e.g. nothing can be green and red all
  over). Why?
• Empiricist creed all knowledge about the world
  comes from the senses.
• The phenomenologians knowledge of necessities
  about the world is supposed to be a priori
  (Wesensschau). LE found this utterly mysterious!

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Logical empiricism (cont)

• There are no true modal statements about the
  world.
• However, there are tautologies, analytic
  statements, whose truth is due solely to the
  definitions of the terms contained.
• In a philosophical coup detat LE substituted
  necessity by analyticity and called it logical
  necessity.
• Nothing can be green and red all over is
  analytic.
• Bachelors are unmarried is accepted as paradigm
  of necessity in the strongest sense.

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Logical empiricism (cont)

• Since then philosophers interpret necessarily p
  as analytically p (or non-p is
  self-contradictory)
• E.g. the question whether backward causation is
  possible is taken to be the question whether A
  at t2 caused B at t1 is self-contradictory.

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(GN) in post-Ayer philosophy

• God exists necessarily is taken to be the claim
  that God exists is analytic.
• Findlay Can Gods existence be disproved
  (1948)
• If God existed he would exist necessarily
• God exists would be analytic
• It is not analytic
• There is no God

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The right response

• It is true that God exists is not analytic.
• True necessity statements are not analytic. The
  kind of necessity relevant for philosophy is
  synthetic necessity.

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Synthetic necessity

• A synthetic necessity claim is one of the form
  necessarily p where p is synthetic.
• Ordinary as well as philosophical modal
  statements are synthetic.
• E.g. the question whether backward causation is
  possible arises only if A at t2 caused B at t1
  is consistent.
• Why are there true synthetic modal statements?

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Synthetic necessity

• Humans have the peculiar ability to conceive of
  things, to form concepts. Further, they can
  combine concepts (consistently) to form new
  concepts.
• Given a concept one can ask whether there is
  something that falls under it.
• For a given concept there is not only the
  question whether there is something that falls
  under it, there is also the question whether it
  is possible that there is something that falls
  under it.
• Hence every existence statement, e.g. there is
  something that is green and red all over or
  There is a God.

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When is x exists necessarily true?

• If x once did not exist it does not exist n.ly
• Something may exist at all times but not exist
  necessarily.
• Something exists necessarily only if it is
  imperishable.
• God is imperishable if
• it is impossible that he will be abolished
• it is impossible that he will commit suicide
• it is impossible that he will cease to exist by
  accident.

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Defence of the premises needed

• God did not begin to exist.
• If he had begun there would be something before
  beyond his control.
• God is imperishable.
• One could defend this by deriving it from
  everlastingness being part of the concept (or
  nature) of God. But that is begging the
  question. It is impossible that God will be
  abolished.
• He is powerful enough to avoid that.
• It is impossible that God will commit suicide.
• He has overriding reason for not doing so.
• It is impossible that God will cease by accident.

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God exists necessarily

• Up to some time in the past, God has always
  existed
• It is impossible that he will be abolished
• It is impossible that he will commit suicide
• It is impossible that he will cease to exist by
  accident.
• God exists necessarily.

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An alternative argument

• God is cause of everything and has no cause
• Hence there is nothing that exists without God
  bringing it into being and sustaining it.
• When there is no God there is nothing.
• Assumption if there are no things, then there is
  no time.
• Hence there is no time when there is no God.

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An alternative argument (cont)

• God is cause of everything and has no cause
• If there are no things there is no time
• God exists necessarily.

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Anselm again

• It is often assumed that Anselms claim that God
  exists necessarily is identical with his claim
  that existence is part of the concept of God. But
  Anselm distinguishes them.
• Anselm x exists necessarily iff x has no
  beginning, x has no end, and x is not made up of
  parts and hence cannot be destroyed (Reply to
  Gaunilo 4)

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Could Gods existence still be a cosmic
accident?

• Some may say Gods existence could still be a
  gigantic cosmic accident (Alston), because it is
  not logically necessary
• LN is not trivially stronger than SN because what
  is logically necessary is not synthetically
  necessary.
• Is the necessity in There cannot be a married
  bachelor really stronger than the necessity in
  Nothing can cause something earlier?

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The lesson

• God exists necessarily (if he exists at all)
• Further suggestions
• Logical necessity is not stronger than synthetic
  necessity
• Logical necessity does not deserve to be called
  necessity
• Modal questions arising in philosophy are about
  synthetic modality