# Finite-Degree Predicates and Two-Variable First-Order Logic

@inproceedings{Paperman2015FiniteDegreePA, title={Finite-Degree Predicates and Two-Variable First-Order Logic}, author={Charles Paperman}, booktitle={CSL}, year={2015} }

We consider two-variable first-order logic on finite words with a fixed number of quantifier alternations. We show that all languages with a neutral letter definable using the order and finite-degree predicates are also definable with the order predicate only. From this result we derive the separation of the alternation hierarchy of two-variable logic on this signature.

## One Citation

### A crevice on the Crane Beach: Finite-degree predicates

- Computer Science2017 32nd Annual ACM/IEEE Symposium on Logic in Computer Science (LICS)
- 2017

First-order logic (FO) over words is shown to be equiexpressive with FO equipped with a restricted set of numerical predicates, namely the order, a binary predicate MSB<inf>0</inf>, and the…

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