Hunter, Geoffrey - Metalogic [PDF]

Metalogic: An Introduction to the Metatheory of Standard First Order Logic
by Geoffrey Hunter
University of California Press, 1973

This clearly written and sometimes even amusing book is a great source for philosophers, mathematicians and logicians interested in the metatheory of logic. It should also be interesting for anyone who's interested in the foundations of mathematics, in philosophy of logic or philosophy of language.
This book is not meant for laymen, but it should be fairly accessible to anyone with basic knowledge in formal logic (Propositional Calculus and Predicate Calculus), not necessarily mathematical logic.

From Amazon.com:
This work makes available to readers without specialized training in mathematics complete proofs of the fundamental metatheorems of standard (i.e., basically truth-functional) first order logic. Included is a complete proof, accessible to non-mathematicians, of the undecidability of first order logic, the most important fact about logic to emerge from the work of the last half-century.
Hunter explains concepts of mathematics and set theory along the way for the benefit of non-mathematicians. He also provides ample exercises with comprehensive answers.


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>Grassyhopper.