Title
From hierarchies to well-foundedness
Abstract
We highlight that the connection of well-foundedness and recursive definitions is more than just convenience. While the consequences of making well-foundedness a sufficient condition for the existence of hierarchies (of various complexity) have been extensively studied, we point out that (if parameters are allowed) well-foundedness is a necessary condition for the existence of hierarchies e.g. that even in an intuitionistic setting $${(\Pi_1^0-\mathsf{CA}_0)_\alpha \vdash \mathsf{wf}(\alpha)\, {\rm where}\, (\Pi_1^0-\mathsf{CA}_0)_\alpha}$$ ( 1 0 - CA 0 ) wf ( ) where ( 1 0 - CA 0 ) stands for the iteration of $${\Pi^0_1}$$ 1 0 comprehension (with parameters) along some ordinal $${\alpha}$$ and $${\mathsf{wf}(\alpha)}$$ wf ( ) stands for the well-foundedness of $${\alpha}$$ .
Year
DOI
Venue
2014
10.1007/s00153-014-0392-9
Archive for Mathematical Logic
Keywords
DocType
Volume
pseudohierarchy,transfinite recursion,well-foundedness,03b30,second order set theory,03e70,03d75,03f35,intuitionistic logic,second order arithmetic
Journal
53
Issue
ISSN
Citations 
7-8
1432-0665
1
PageRank 
References 
Authors
0.39
0
2
Name
Order
Citations
PageRank
Dandolo Flumini110.39
Kentaro Sato242.17