Does one have to understand the theory of formal ontologies and logic to use the Semantic Web?
First of all, as pointed out elsewhere in this document, one can develop Semantic Web applications without using ontologies. Very useful applications can be built without those, relying on the most fundamental, and simple concept of the Semantic Web. However, even if ontologies, rules, reasoners, etc, are used, the average user should not care about the complexities of, say, the details of reasoning. All this is done “under the hood”. What the developer needs to operate with are usually simple logical patterns of the sort “Given that (Flipper isA Dolphin) and (Dolphin isAlso Mammal), one can conclude that (Flipper isA Mammal)”. Compare it to SQL. The official SQL standards, the formal semantics of SQL, and indeed its implementations, are extremely complex and understood by a few specialists only. Nevertheless, a large number of users use SQL in practice, without caring about the underlying complexities.
