On Logics with Two Variables

@article{Grdel1999OnLW,
  title={On Logics with Two Variables},
  author={Erich Gr{\"a}del and Martin Otto},
  journal={Theor. Comput. Sci.},
  year={1999},
  volume={224},
  pages={73-113}
}
  • E. Grädel, M. Otto
  • Published 6 August 1999
  • Computer Science, Philosophy
  • Theor. Comput. Sci.

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On the Restraining Power of Guards

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    Journal of Symbolic Logic
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It is proved that the satisfiability problems for the guarded fragment and the loosely guarded fragment of first-order logic are complete for deterministic double exponential time and that some natural, modest extensions of the guarded fragments are undecidable.

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