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# 3: Logic

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formal logic

You can write any letters you choose;
Formal logic, though, like $$p$$'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

In this chapter, we will introduce some of the basic concepts of mathematical logic. In order to fully understand some of the later concepts in this book, you must be able to recognize valid logical arguments. Although these arguments will usually be applied to mathematics, they employ the same techniques that are used by a lawyer in a courtroom or a physician examining a patient. An added reason for the importance of this chapter is that the circuits that make up digital computers are designed using the same algebra of propositions that we will be discussing.

3: Logic is shared under a CC BY-NC-SA license and was authored, remixed, and/or curated by Al Doerr & Ken Levasseur.