This book addresses problem like: Can we prove all that is true? Can symbolic manipulation capture everything? Is there a general method to solve a class of solvable problems? Is mathematics contradictory? To answer these fundamental questions, it comes up with results such as Deduction, reductio ad absurdum, Monotonicity. Compactness, Completeness, Undecidability and Incompleteness as expounded in the works of Herbrand, Godel, Skolem, Lowenheim, Beth, Tarski, ...