my friend bet me $ 20 in a swimming race across a lake last weekend . i took the deal because i am positive i 'm a stronger swimmer ! $ 20 bucks ? i 'd try to do it too . how 'd it go ? ? i won of course ! the guy was no match for my swimming speed ! awesome ! he 'll know not to challenge you next time ! $ 20 bucks richer !
The person's belief in their superior swimming abilities caused their feeling of confidence.