FAITH... WITH REASON

Your definition said: "complete trust or confidence in someone or something." "Complete trust or confidence" is "certainty." What in the world else would it be? 

Look, all these different examples aren't getting us anywhere. The simple point is that people can and do act all the time on all kinds of things without "complete trust or confidence" in whatever they're doing. All you're doing is posting examples of people having enough trust or enough confidence to do what they're doing because the risk is worth the reward. This is only faith if you convince yourself there is no risk. 

But there shouldn't even be the need for debate. Complete is pretty damn unambiguous, and I can't imagine what you think "complete trust" could mean other than "certainty." Further, I don't understand why you don't understand people can act on all kinds of things they have very little trust in. All of my betting examples demonstrate this pretty conclusively. In neither the dice nor coin-flip situation are you confident at all you'll win; you simply conclude that the risk is worth the reward and do it. 

Exactly, and yet you choose to drive your car knowing an accident is possible. That's what I mean by the ability to act on such things without faith and while recognizing the risk involved. All your examples are cases of where there's risk that an individual decides is worth taking for whatever reasons; not situations where they have "faith" the risk isn't there. 

I wasn't thinking of it in terms of what, specifically, lies beyond the bridge... I just assumed that in coming to the bridge you had some reason you wanted to cross it to begin with. You mentioned other people, so maybe you're mountain climbing with friends and want to continue to journey with them. In that case, the "reward" of continuing on with your friends maybe worth whatever risk you think there is in plummeting to your death. Not really sure what you mean with the "how much you are willing to risk..." part. 

But it's not "blind dumb luck" to rely on math. My point with the dice example was in showing how you can act on something where you're likely to lose because the risk is worth the reward. I even showed how this was so mathematically. This mentality comes from my years of playing poker professionally, which is a game of nothing but risk/reward. My decisions aren't based on my "faith" that I know my hand is good or no good, or my "faith" that my opponent has X or Y; it's based on my understanding of the underlying math and this risk/reward paradigm. In fact, I make money from people who only act on "faith" and think they can accurately guess when they're best or when their opponents are bluffing. 

I think this can apply to just about anything in life. Not all decisions come down to how confident you are in a positive outcome, since the risk/reward tends to determine how uncertain the outcome can be until you're no longer willing to do it. To go back to the dice, you can't just ask me to bet on it coming a 6; I have to know how much I'm risking and how much I stand to win. If I stand to win more than 5:1, then it's worth it. Obviously in life we rarely have these precise, mathematical numbers, but we do still intuitively try to gauge how much we're risking against whatever possible reward there is, compare that to how certain we are of any outcome, and act accordingly. You can do this without "faith," without having any high (much less "complete") confidence that something will turn out how we hope.