John MacFarlane
Professor of philosophy at UC Berkeley, working on logic and the philosophy of language, and elected a Fellow of the American Academy of Arts and Sciences in 2015. He is also the author of Pandoc, the document converter, and one of the people who launched CommonMark in 2014; he remains a current lead and the spec is published under his name.
The pairing is not decoration. Writing a grammar for a format that had only ever been defined by a buggy Perl script is a problem in formal specification — deciding what a string of asterisks means before deciding what a parser should do with it, and the person who took it on works professionally on how sentences get their content. This spoke's other format specs came out of engineering organizations; this one came out of a philosophy department by way of a document converter.
Related
Cross-spoke: ../philosophy-wiki owns philosophers and their systems, and ../research-wiki owns
the mechanizing-reasoning lineage. Neither holds him yet. His philosophical work (assessment
sensitivity, relativism about truth) is not sourced anywhere in this corpus, and is recorded here only
as the affiliation behind the specification.