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FOPL, Logically

The first thing you need to know about a logic is its syntax. A logic’s syntax tells you, formally, how to read and write sentences in that logic. Syntax doesn’t tell you how to understand the statements or what they mean. It just tells you what they look like and how to correctly put them together.

Logic separates the meaning of the statements from the syntax. The meaning is called the semantics of the logic. For FOPL, the semantics are pretty easy to follow—not because they’re really all that simple, but because you use them every day. Most arguments, most bits of reasoning that you hear every day, are FOPL, so you’re used to it even if you don’t realize it.

We’re going to walk through the basic syntax and semantics of ...