necessary
“1837 Louis Viardot, L’Ingénieux Hidalgo Don Quichotte de la Manche, translation of El ingenioso hidalgo Don Quijote de la Mancha by Miguel de Cervantes Saavedra, Chapter I” — It seemed to him appropriate and necessary, as much for his own glory as for the service of his country, that he should become a knight-errant, and go about the world, with his horse and his weapons, looking for adventures, and practising everything that he had read that knights-errant practised, redressing all sorts of wrongs, and exposing themselves to so many encounters, to so many perils, that he should gain, in surmounting them, eternal fame. He already imagined himself, the poor dreamer, seeing himself crowned at least by the emperor of Trebizond. So carried away was he by such pleasant thoughts and by the ineffable attraction that he found in them, he hurried to put his desire into practice.
Related: condition nécessaire, mal nécessaire, nécessairement