8 found
  1.  72
    A Guide to Truth Predicates in the Modern Era.Michael Sheard - 1994 - Journal of Symbolic Logic 59 (3):1032-1054.
  2.  20
    Elementary Descent Recursion and Proof Theory.Harvey Friedman & Michael Sheard - 1995 - Annals of Pure and Applied Logic 71 (1):1-45.
    We define a class of functions, the descent recursive functions, relative to an arbitrary elementary recursive system of ordinal notations. By means of these functions, we provide a general technique for measuring the proof-theoretic strength of a variety of systems of first-order arithmetic. We characterize the provable well-orderings and provably recursive functions of these systems, and derive various conservation and equiconsistency results.
    Direct download (4 more)  
    Export citation  
    Bookmark   20 citations  
  3.  67
    Weak and Strong Theories of Truth.Michael Sheard - 2001 - Studia Logica 68 (1):89-101.
    A subtheory of the theory of self-referential truth known as FS is shown to be weak as a theory of truth but equivalent to full FS in its proof-theoretic strength.
    Direct download (5 more)  
    Export citation  
    Bookmark   9 citations  
  4.  14
    The Equivalence of the Disjunction and Existence Properties for Modal Arithmetic.Harvey Friedman & Michael Sheard - 1989 - Journal of Symbolic Logic 54 (4):1456-1459.
    In a modal system of arithmetic, a theory S has the modal disjunction property if whenever $S \vdash \square\varphi \vee \square\psi$ , either $S \vdash \square\varphi$ or $S \vdash \square\psi. S$ has the modal numerical existence property if whenever $S \vdash \exists x\square\varphi(x)$ , there is some natural number n such that $S \vdash \square\varphi(\mathbf{n})$ . Under certain broadly applicable assumptions, these two properties are equivalent.
    Direct download (8 more)  
    Export citation  
    Bookmark   3 citations  
  5.  36
    Anil Gupta and Nuel Belnap. The Revision Theory of Truth. Bradford Books. The MIT Press, Cambridge, Mass., and London, 1993, Xii + 299 Pp. [REVIEW]Michael Sheard - 1995 - Journal of Symbolic Logic 60 (4):1314-1316.
  6.  26
    Indecomposable Ultrafilters Over Small Large Cardinals.Michael Sheard - 1983 - Journal of Symbolic Logic 48 (4):1000-1007.
  7. Truth and Trustworthiness.Michael Sheard - 2015 - In Kentaro Fujimoto, José Martínez Fernández, Henri Galinon & Theodora Achourioti (eds.), Unifying the Philosophy of Truth. Springer Verlag.
    Export citation  
  8.  23
    Co-Critical Points of Elementary Embeddings.Michael Sheard - 1985 - Journal of Symbolic Logic 50 (1):220-226.
    Probably the two most famous examples of elementary embeddings between inner models of set theory are the embeddings of the universe into an inner model given by a measurable cardinal and the embeddings of the constructible universeLinto itself given by 0#. In both of these examples, the “target model” is a subclass of the “ground model”. It is not hard to find examples of embeddings in which the target model is not a subclass of the ground model: ifis a generic (...)
    Direct download (8 more)  
    Export citation