In formal logic, we develop different systems of symbols and rules to express ideas and carry out proofs. There are lots of such formal systems. In this module we discuss Sentential Logic (SL). It is one of the simplest formal systems of logic, and is also known as "Propositional Logic".

## Tutorials

- [SL01] Introduction
- [SL02] Well-formed formula
- [SL03] Connectives
- [SL04] Complex truth-tables
- [SL05] Properties & relations
- [SL06] Formalization
- [SL07] Validity
- [SL08] The indirect method
- [SL09] Indirect method: exercises
- [SL10] Material conditional
- [SL11] Derivations
- [SL12] Derivation rules 1
- [SL13] Derivation rules 2
- [SL14] List of derivation rules
- [SL15] Derivation strategies
- [SL16] Soundness
- [SL17] Completeness
- [SL18] Limitations

### Before you begin

Please check that your browser can display the logic symbols used in this module. These are the symbols:

≡ | ∨ | ↔ | → | ∃ | ∀ | ψ | φ | α | β | ⊧ |

They should look like the ones in this picture:

If not, try a more advanced browser, such as Chrome.

## What next?

After you have finished this module, try our next module on predicate logic!