Robinson Arithmetic

In mathematics, Robinson arithmetic, or Q, is a finitely axiomatized fragment of Peano arithmetic (PA), first set out in R. M. Robinson (1950). Q is essentially PA without the axiom schema of induction. Since Q is weaker than PA, it is incomplete. Q is important and interesting because it is a finitely axiomatized fragment of PA that is recursively incompletable and essentially undecidable.

Read more about Robinson Arithmetic:  Axioms, Metamathematics

Famous quotes containing the words robinson and/or arithmetic:

    He set the jug down slowly at his feet
    With trembling care, knowing that most things break;
    —Edwin Arlington Robinson (1869–1935)

    I hope I may claim in the present work to have made it probable that the laws of arithmetic are analytic judgments and consequently a priori. Arithmetic thus becomes simply a development of logic, and every proposition of arithmetic a law of logic, albeit a derivative one. To apply arithmetic in the physical sciences is to bring logic to bear on observed facts; calculation becomes deduction.
    Gottlob Frege (1848–1925)