The term "logic" is often used in many different ways. It is sometimes understood broadly as the systematic study of the principles of good reasoning. As such logic is not very different from critical thinking. But sometimes "logic" is understood more narrowly as what we might call "deductive logic". Roughly speaking, deductive logic is mainly about the consistency of statements and beliefs, as well as the validity of arguments. These are the topics we shall investigate in the following modules.

## Tutorials

## Modules on formal logic

Formal logic is the study of logic using special symbols and clearly-defined rules of reasoning. They are very useful in linguistics, philosophy, artificial intelligence and mathematics. The tools of formal logic can also help us formulate ideas and arguments more precisely. In our web site we introduce two of the most basic systems of formal logic.

## Other logic modules

## Logic puzzles

- Fun logic puzzles
- Knights and Knaves puzzles (382 of them!)
- The World's hardest logic puzzle Warning: It's really tough!

## Further reading

- See this page from Joe Lau for a list of textbooks on formal logic.
- Entries on logic in the Stanford Encyclopedia of Philosophy - These are articles that discuss some of the main issues in the philosophy of logic. They are difficult!
- A very good place to start if you want to study formal logic systematically is the textbook
*A Modern Formal Logic Primer*by Paul Teller. It is now out of print but the author has generously made it available for free online at: http://tellerprimer.ucdavis.edu/ - Book recommendations on logic