A scientific hypothesis starts the process of scientific enquiry. False hypotheses can start the path to disaster, as was seen with the geocentric model of the'universe' in which heavenly bodies moved in circular orbits. It became heresy to suggest that orbits aren't circular around the stationary earth, leading to epicycles. It's a good story worth studying in school to appreciate how a hypothesis is critical to validating science. Here's an important hypothesis: "The fundamental aim in the linguistic analysis of a language L is to separate the grammatical sequences which are the sentences of L from the ungrammatical sequences which are not sentences of L and to study the structure of the grammatical sequences."