Somebody is offered a new job and he has to make a decision whether to leave his old job and take the new one. He examines all the "evidence" and makes a decision. Are you saying that this is an irrational procedure?
Yes, to a point. Most people make decisions like that based somewhat on emotionals and somewhat on rational thought, that is what it is to be human. In you example there isn't necessarily just evidence going into the mix, there is how he 'feels' about the job, the people, the location, etc. These aren't evidence, they're emotions.