General First Order Languages

• There is not one first order language, but many.
• A first order language is specified by fixing the names, predicates and function symbols (along with their respective arities).
• There must be at least one predicate symbol. Everything else is optional.
• Sometimes, the specification is already supplied. At other times (e.g. when translating from English into FOL), it has to be designed.
• Designing a first order language with just the right names, predicates and function symbols requires some skill

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