Consider the solution below to this: "Prove that if A is a set then so is {A} but do NOT use an argument that involves stages explicitly". "Proof." We know (NOTEs!) that, for any sets A and B, {A, B} is a set. But {A} ≤ {A, B}, so {A} is a set by the subclass theorem. What EXACTLY is wrong with the proof above?

Consider the solution below to this: "Prove that if A is a set then so is {A} but do NOT use an argument that involves stages explicitly". "Proof." We know (NOTEs!) that, for any sets A and B, {A, B} is a set. But {A} ≤ {A, B}, so {A} is a set by the subclass theorem. What EXACTLY is wrong with the proof above?

Database System Concepts

7th Edition

ISBN:9780078022159

Author:Abraham Silberschatz Professor, Henry F. Korth, S. Sudarshan

Publisher:Abraham Silberschatz Professor, Henry F. Korth, S. Sudarshan

Chapter1: Introduction

Section: Chapter Questions

Problem 1PE

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