Phonetics prescribes how to combine sounds so as to form spoken words correctly. Spelling prescribes how to combine letters so as to form written words correctly. Grammar prescribes how to combine words so as to form sentences correctly. Rhetoric prescribes how to combine sentences into paragraphs and paragraphs into a whole composition having unity, coherence, and the desired emphasis, as well as clarity, force, and beauty. Logic prescribes how to combine concepts into judgments and judgments into syllogisms and chains of reasoning so as to achieve truth