Set theory has many applications in mathematics and other fields. Example 1.5.1 If the universe is $\Z$, then $\{x:x>0\}$ is the set of positive integers and $\{x:\exists n\,(x=2n)\}$ is the set of even integers. Show that the Pair-Set Axiom is deducible from the Axioms o f Empty-Set, Power-Set and Replacement. Logic and Set Theory To criticize mathematics for its abstraction is to miss the point entirely. Logic and Set Theory Examples 1 PTJ Michaelmas 2012 Important Note: There are probably more questions on these example sheets than any one student will wish to attempt, and they are not intended to be all of the same level of diﬃculty. If you concentrate too closely on too limited an application of a mathematical idea, you rob the mathematician of his most important tools: analogy, generality, and simplicity. Lent 2015 LOGIC AND SET THEORY { EXAMPLES 4 IBL 1. Important Note: There are probably more questions on these example sheets than any one student will wish to attempt, and they are not intended to be all of the same level of difficulty. 2. Leader Notes taken by Dexter Chua Lent 2015 These notes are not endorsed by the lecturers, and I have modi ed them (often signi cantly) after lectures. Abstraction is what makes mathematics work. PTJ Michaelmas 2012. For example, the two descriptions \is a man" and \is a male homo sapiens" both describe the same set, viz. Show that the Empty-Set Axiom is deducible from the Axioms of In nity and Separation (or, if you prefer, just from the Axiom of In nity), and that t he Axiom of Separation is deducible from the Axiom of Replacement. Also, the set theory is considered as the foundation for many topics such as topology, mathematical analysis, discrete mathematics, abstract algebra, etc. No speci c prerequisites. Part II | Logic and Set Theory Based on lectures by I. They are nowhere near accurate representations of what was actually lectured, and in particular, all errors are almost surely mine. Set theory, branch of mathematics that deals with the properties of well-defined collections of objects, which may or may not be of a mathematical nature, such as numbers or functions.The theory is less valuable in direct application to ordinary experience than as a basis for precise and adaptable terminology for the definition of complex and sophisticated mathematical concepts. 3. Logic and Set Theory Examples 1. It was this objecti cation of meaning, under- standing properties as sets, that led to a rebirth of Logic and Mathematics in the 19th century. If there are a finite number of elements in a set, or if the elements can be arranged in a sequence, we often indicate the set simply by listing its elements. – Ian Stewart Does God play dice? the set of all men. Boole was to assign a meaning as a set to these descriptions. Logic and Set Theory: Example Sheets Thomas Forster May 10, 2020 They are used in graphs, vector spaces, ring theory, and so on. B. All these concepts can be defined as sets satisfying specific properties (or axioms) of sets.