The Principles of Mathematics RevisitedThis book, written by one of philosophy's preeminent logicians, argues that many of the basic assumptions common to logic, philosophy of mathematics and metaphysics are in need of change. Jaakko Hintikka proposes a new basic first order logic and uses it to explore the foundations of mathematics. This new logic enables logicians to express on the first order level such concepts as equicardinality, infinity, and truth in the same language. Hintikka's