🌐EnglishEnglishDeutschEspañolFrançaisItalianoNederlandsPolskiPortuguêsSvenskaTiếng ViệtTürkçeРусскийالعربيةفارسیहिन्दी한국어中文日本語EntityQ852732· pop 29· linked from 458 articlesproof theoryAlso known as proof systemsbranch of mathematical logicAvailable in 29 languagesEspañolFrançaisDeutsch中文日本語РусскийPortuguêsItalianoالعربيةहिन्दीConnectionsnatural deductionEntityPeano axiomsEntityCategoriesMathematical logicMetalogicProof theory