lean-ja / lean-ja/lean-by-example
Typeが可述的だとどう矛盾するのか？
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データ型
要調査
- Dominant language
- Lean
- Stars
- 188
- Forks
- 15
- Avg merge
- 9h 8m
- Merged PRs (30d)
- 6
Description
Typeの非可述性を仮定すると矛盾を生む。
一方で Prop は非可述的でも矛盾を生まないのはなぜか？証明無関係のおかげか？
これを理解するには、そもそもTypeが可述的だとどう矛盾するのかを知る必要がある。
Contributor guide
First steps
- Read the whole issue, then the project's contributing guide.
- Comment on the issue to say you are picking it up — it saves two people doing the same work.
- Fork the repository and make your change on a branch.
- Open a pull request that references the issue number.
Research direction
The issue contains a conceptual question about why assuming Type is impredicative leads to a contradiction while Prop does not. Start by researching the Type and Prop distinction in Lean's theorem-proving documentation; done means documenting a clear explanation that addresses both questions, since no file or test is named.
Written by the indexing model from the issue text.
Assessment
- Domain
- documentation
- Issue type
- Documentation
- Difficulty
- 5/5
- Estimated time
- Over a week
- Activity status
- Stale
- Clarity
- Needs clarification
- Newbie friendliness
- 25/100