Wisdom abides the spaces of doubt
What do I mean?
Regarding most kinds of propositions that humans believe, we cannot obtain epistemic certainty. Hence, for most topics, one’s belief – even if reasonable – might be false. The wise recognize this fact, accept it, and adjust accordingly the degree of (subjective) confidence they place in each of their beliefs. The wise thus don’t claim certainty if aware that they lack it.
Now, as I am using ‘doubt,’ the term refers to one’s awareness that he lacks epistemic certainty and thus might be wrong. If one is conscious that epistemic certainty about proposition p is unavailable and yet has reason to believe that the probability of p’s being true is above .5 but below 1, his belief will similarly fall into a confidence space of above 50 and below 100%. He will realize that he might be wrong, though he is probably right. This realization explains his room for doubt, which fills the gap between being certain that p and merely believing that p.
Suppose that Sage Smith has reason to affirm that p is probably true to the degree of .7. Yet, ever cognitively vigilant, he recognizes that epistemic certainty concerning p is absent for us humans, and therefore that p is not probable to the degree of 1. He thus believes that p, and correspondingly places 70% confidence in his belief that p is true while acknowledging that there is a lacuna of 30% between his confidence level and certainty. His doubt lives fruitfully in that fairly large gap. In this sense, doubt is consistent with belief. Sage Smith abides his spaces of doubt.
As Pope put it, “How prone to doubt, how cautious are the wise!” (The Odyssey of Homer, translation, Book 8, Line 375)