Synonyms to fundamental idea

guiding principle, big idea, canon, code, commandment, convention, course, creed, dictum, form, formula, general principle, golden rule, guideline, guiding principles, idee-maitresse, imperative, law, leading idea, line, main idea, maxim, mitzvah, moral, norm, ordinance, plan of action, platform, policy, polity, position paper, principal idea, principium, principle, principles, procedure, regulation, rubric, rule, settled principle, standard, tenet, working principle, working rule