Slopfest #5 · 1931 · Vienna

This Festival Cannot Be Proven

Some true statements can't be proven. Our attendance figures are among them.

Framed café napkin, extreme close-up: dense fountain-pen logic symbols circling the only legible words, 'SLOPFEST #5: true, not provable'

Venue: University of Vienna, a lecture hall nobody could find
Attendance: 38
Guest of honour: Kurt Gödel (filled a napkin with symbols the committee still cannot read)
Fun fact: 1 napkin, framed, still undecidable

What happened

Kurt Gödel spent the evening in a corner filling a napkin with symbols, and the committee took the napkin as an endorsement. The program was later found to contain a statement that was true but could not be proven true using only the program. The committee has used this as its legal defense ever since, most often in November.

Elsewhere in 1931

Viennese logician Kurt Gödel publishes his incompleteness theorems: some true statements cannot be proven within a system.

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