inexplicable

La poésie est une quête de l'inexplicable.

Poetry is a search for the inexplicable.

Tom était habituellement très fiable et son absence à la réunion était inexplicable.

Tom was normally very reliable and his absence from the meeting was inexplicable.

À trop vouloir expliquer l'inexplicable, on finit par excuser l'inexcusable.

When anyone tries to explain the inexplicable, he is getting ready to excuse the inexcusable.

Elle ne l'aimait pas, elle ne l'aimerait jamais; il lui inspirait une secrète et inexplicable aversion.

She didn't love him, she would never love him; he has inspired in her a secret and inexplicable dislike.