Pauline doubt, which tests everything in order to hold fast to what is good, is hard work. But it does not doubt that there is a good to be found, and does not doubt the standards for the test.
Cartesian doubt, which doubts everything except what literally cannot be doubted, is not honest. If it were, it would admit that there is nothing which cannot be doubted, not even the famous cogito, ergo sum. So it could never even begin to advance toward the truth.
But the cool, relativist doubt of our own time, which is content to believe that no one can know the truth anyway, is lazy and incoherent: Incoherent, because it claims to know nothing can be known; lazy, because it no longer bothers to seek knowledge.