# Introduction to Proofs, Spring 2022

Johns Hopkins University

### Sina Hazratpour

- Office Hours: Wednesdays 3:00pm-4:00pm
- By appointment only: Schedule time with me or email me.

## Week 13 Announcements

## Propositional Logic

- Jan 24
- Introduction to MATH301
- Jan 28
**Section**- Lean Installation Party

- Jan 26
**Propositions, Part II**- Section 1.1. and Appendix D

- We shall introduce propositional logic and we shall analyze the
**forms of proofs**. We shall focus on propositional formulae formed by logical connectives and introduce new tools such as parsing trees to aid us with complicated propositional formulae. - Jan 31
**HW 1 due**- HW1

## Natural Deduction in Lean

- Jan 31
**Natural Deduction in Lean, Part 1**- Feb 4
**Section**- Feb 2
**Natural Deduction in Lean, Part 2**

## Classical Reasoning

- Feb 7
**The Law of Excluded Middle and Proof by Contradiction**- Feb 11
**Section**- Feb 9
**Other Classical Principles of Reasoning**- Feb 14
**HW 2 due**- HW2

## Predicate Logic

- Feb 14
- Feb 18
**Section**- Feb 16
- Feb 23
**HW 3 due**- HW3

## Predicates On Natural Numbers

- Feb 21
- Feb 25
**Section**- Feb 23
- Chapter 4 of textbook
- Mar 7
**HW 4 due**- HW4

## Sets

- Feb 28
- Mar 4
**Section**- Mar 2
- Mar 14
**HW 5 due**- HW5

## More on Sets

- Mar 7
- Mar 11
**Section**- Mar 9
- Mar 14
**HW 5 due**- HW5

## Sets in Lean

- Mar 14
**Basic Operations on Sets**- Mar 18
**Section**- Mar 16
**Tactics**- Mar 28
**HW 6 due**- HW6

## Functions

- Mar 28
- Apr 1
**Section**- Mar 30
- Apr 12
**HW 7 due**

## Functions in Lean

## Midterm Exam Week

## Relations

- Apr 18
**Equivalence Relation**- Apr 22
**Section**- Apr 20
**Quotient by Equivalence Relation**- Apr 25
**HW 8 due**- HW8