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Typechecking is undecidable when 'type' is a type (1989) [pdf]

by zem on 1/30/2026, 5:31:29 AM

https://dspace.mit.edu/bitstream/handle/1721.1/149366/MIT-LCS-TR-458.pdf?sequence=6

Comments

by: moomin

It feels like this is unsurprising, given we already have Goedel's theorems and halting theorems. Any system of self-describing complexity ends up in this territory.

2/1/2026, 10:15:55 PM


by: Animats

This sounds close to Russell's "class of all classes" paradox. Is it?

2/1/2026, 8:48:29 PM


by: randomNumber7

And still this type system could be the base for a very interesting and powerfull programming language imo.

2/1/2026, 10:21:14 PM


by: cwmoore

Similar to the difficulty in finding Title Search companies on Indeed.

2/1/2026, 8:50:11 PM


by: marcosdumay

Hum... I'm getting 403, forbiden. Is it down?

2/1/2026, 9:05:13 PM