Thinking in Bets
Beliefs are bets on the future.
If we think of our belief/decision as bets, we would be more open to challenge/change it, rather than be tied to it.
Good way to challenge a belief is to ask "How much will you bet on that?"
If we have a certainty of belief, we will automatically dismiss opposing ideas(Motivated Reasoning/Confirmation Bias). Its better to have a belief that you are X% sure is true. If there is new information that affirms your belief, you increase your number. If you find evidence against the belief, you decrease the number.
If we don't have a certainty of belief, we'll be more likely to search for more information or help. If we are certain, we will not search further
If you are worried that doing this will erode your confidence, you don't need that type of Confidence to Convince Others.