In
modal logic
Modal logic is a kind of logic used to represent statements about Modality (natural language), necessity and possibility. In philosophy and related fields
it is used as a tool for understanding concepts such as knowledge, obligation, and causality ...
, modal collapse is the condition in which every true statement is
necessarily true, and vice versa; that is to say, there are no
contingent truths, or to put it another way, that "everything exists necessarily"
(and likewise if something does not exist, it cannot exist). In the notation of modal logic, this can be written as
.
In the context of philosophy, the term is commonly used in critiques of
ontological arguments for the existence of God and the principle of
divine simplicity
In classical theistic and monotheistic theology, the doctrine of divine simplicity says that God is simple (without parts). God exists as one unified entity, with no distinct attributes; God's existence is identical to God's essence.
Overview
...
.
For example,
Gödel's ontological proof contains
as a theorem, which combined with the axioms of
system S5 leads to modal collapse. Since some regard
divine freedom as essential to the nature of God, and modal collapse as negating the concept of
free will
Free will is generally understood as the capacity or ability of people to (a) choice, choose between different possible courses of Action (philosophy), action, (b) exercise control over their actions in a way that is necessary for moral respon ...
, this then leads to the breakdown of Gödel's argument.
References
Collapse
Philosophical logic
Theology
Necessity
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