As we saw in Chapter 1, computers have a reputation—not always deserved—for being ‘logical’. But fundamentally, deep down, they are made of logic in a very real sense. The building blocks of computers are logic gates, which are electronic components that compute the values of simple propositions such as p ∧ q and ¬p. (Each gate is in turn built of even smaller electronic components called transistors, but this needn’t concern us here: see the course Computer Organisation.)
Don’t worry, logic circuits will be examined in Computer Organisation, not in Reasoning & Logic. They are a good example and application of propositional logic, and that’s why we’re talking about them in this section. Normal forms (Section 2.3.4) are definitely on the syllabus, however, so pay attention!