It is indistinguishable forever. Smullian R.

The book proposes a fascinating introduction into symbolic logic. The unified interpretation of three “possible worlds” is given: the epistemic world of human beliefs in the truth of statements; The world of machines that can reproduce true statements, and the world of mathematical systems in which the statements can be proved. A non -standard exposition of Gödel's famous theorems of the incompleteness of formal systems and the Lyoba theorems and a fascinating analysis of the relationship between the concepts of “consistency”, “provisability” and “perceptibility”.

This book for those who wish: - not only learn to learn how to learn Successfully look for his friend, who sometimes flies to the islands, inhabited by the knights and shamelessly lying rings, but even become a master in this matter, no worse than detectives from Scotland Yard; - to show off in the company of intellectuals with your non -standard understanding of the essence of the famous results from the field of mathematical logic, known as the theorems of Gödel about the incompleteness and the Lyoba theorem; - Solving fascinating tasks, get acquainted with a serious scientific discipline called “symbolic logic”; - get acquainted with modal logic in the form of “possible worlds” - worlds of human opinions or beliefs; Understand what difficulties in wait for us in the proof of the consistency of our reasoning and in discussions about the consistency of our evidence.