nprofile1qy2hwumn8ghj7un9d3shjtnyd968gmewwp6kyqpqjd874v63430gng67kpw5m597f34dr9vr0yhkp8dkmnma8208raysj9xuzd (nprofile…xuzd) I'm mostly doing algebraic geometry, so well-founded trees and so on don't really appear in the mathematics I'm used to. I do like constructive mathematics (probably in something like IZF, although I like the ideas of type theory) and I'm always a bit appalled by those well-founded trees, because I associate them with something like Zorn's lemma, which IIRC proves their existence in classical set theory?
I'm always a bit surprised that many constructive-friendly type theorists don't seem to have an issue with W-types, is there a reason for this?
Jakob
npub1at…90vsp
2026-02-09 16:22:51 UTC
in reply to nevent1q…8t9v
Author Public Key
npub1at4g3kglwemnmyl7puvfkh6lvtukglp0wtvj0ql6uy67wuuwdjusn90vspPublished at
2026-02-09 16:22:51 UTCEvent JSON
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