This is a tricky question for me because on one hand I am aware of the secret in life. However, the realist in me thinks that being overly positive while gambling is probably not the right move to make a majority of the time. The secret is hard to deny though, as I myself have found me to be a beneficiary of its awesomeness.
I didn't see the question as what you said, because gambling is something that we can't know or comprehend how the winning come but we know that we must win while gambling, I think major thing there is to properly do their analysis well before either making bet or something to lead start gambling without knowing more things about the entire processes.
And yes, staying positive is something very essential while gambling be we shouldn't be overwhelmed with what is in our heart to make winning at a regular basis.