ONTOLOGICAL A.L.Y.K LOCK

Can we, according to all logic (in the broad sense that takes absolutely Everything into account), consider anything whatsoever ('Is' here being the ontological prefix, in its certain uniqueness, of absolutely Everything) without first possessing total certainty (a key of logical certainty, without which how can anything be considered logically)? Does not every assertion/information/affirmation (without the key), by logic alone, collapse doubly? First, for having affirmed with certainty (without the key), but also for having wrongly implied the possession of this Key of Certainty?