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## Read the Online Textbook for the full content.

## Chapter 3 Logic

## formal logic

You can write any letters you choose;
Formal logic, though, likes \(p\)'s and \(q\)'s
To form statements — a lot,
Using IF, OR, AND, NOT —
To determine the falses and trues.
Goldie, The Omnificent English Dictionary In Limerick Form

- Basic concepts of mathematical logic needed to recognize valid logical arguments.
- Logic and the algebra of propositions are used to design digital circuits.
- Essential for designing algorithms and for writing correct code.
- Program control (branches and loops) are driven by logic.
- Math techniques also employed lawyers or physicians examining patients.
- Used universally in science to formulate hypotheses and to draw conclusions.
- Misused in politics and to present bogus arguments for misinformation and propaganda.
- We need to learn the fundamental concepts and the rules of propositional logic.