27 lines
No EOL
922 B
Markdown
27 lines
No EOL
922 B
Markdown
logic
|
|
=====
|
|
|
|
Logical constructions and theorems, beyond what has already been
|
|
declared in init.datatypes and init.logic.
|
|
|
|
The command `import logic` does not import any axioms by default.
|
|
|
|
* [connectives](connectives.lean) : the propositional connectives
|
|
* [eq](eq.lean) : additional theorems for equality and disequality
|
|
* [cast](cast.lean) : casts and heterogeneous equality
|
|
* [quantifiers](quantifiers.lean) : existential and universal quantifiers
|
|
* [identities](identities.lean) : some useful identities
|
|
* [instances](instances.lean) : class instances for eq and iff
|
|
* [subsingleton](subsingleton.lean)
|
|
* [default](default.lean)
|
|
|
|
The file `choice.lean` declares a choice axiom, and uses it to
|
|
prove the excluded middle, propositional completeness, axiom of
|
|
choice, and prove that the decidable class is trivial when the
|
|
choice axiom is assumed.
|
|
|
|
* [choice](choice.lean)
|
|
|
|
Subfolders:
|
|
|
|
* [examples](examples/examples.md) |