Richard A. Posner, in his review of Animal Spirits, writes:
The word "emotional" has overtones of irrationality, but actually emotion is at once a form of telescoped thinking (it is not irrational to step around an open manhole "instinctively" without first analyzing the costs and benefits of falling into it) and a prompt to action that often, as in the case of investment under uncertainty, cannot be based on complete or even good information and is therefore unavoidably a shot in the dark. We could not survive if we were afraid to act in the face of uncertainty.
Indeed. It is incorrect to view emotions as wholly harmful to rational, sound thinking.
Here's my old post The Role of Emotions and Feelings in Decision Making as it applies to concocting a new business idea.